My backup vehicle, a '90 Buick developed a start/stall condition.  The below series of screen pictures from a OTC Solarity shows the 5V Bypass drop, ICM pulls the EST low but both return only to finally quit for good.  Also shown is Ref(Hi) from the ICM to ECM and the 1X output from the crank position sensor.

The same thing happened in '03 but I was getting a DTC 42 but not this time.  I've read that if it happens fast enough, it won't set the code.

Checked voltage drops on grounds at ECM and all are good.  I'm about ready to pull the ECM as I did in '03.  The annoying thing is that there is only 5K miles on this ECM!

Am I missing anything??

Randy H. wrote on Sep 9^th, 2011 at 1:23pm:

Yes, it has a crank sensor, that's what the Ref(Hi) is.  The ICM output from the crank sensor to the ECM and the signal is constant when the Bypass drops to zero.

How do you put it into Bypass mode?

The vehicle is used for family loan outs when their main vehicle is in a shop, etc.

It sat for year without driving on a float charger.  Time for a loan out but battery was dead.  Battery and alternator, out for two weeks, back for two months, out to my sister for a few days.  She past it to her son who started to have a rough idle and stall.  My Bro-in-Law rescued him but got it back to me by using quick start several times.

Two days later, it starts right up!  I looked at the fuel pump, FPR, etc. for a week with it starting up every time.  Then it started to stall and then start/stall now while never leaving my garage.

Retired wrote on Sep 9^th, 2011 at 1:58pm:


All you do is extract the EST wire from the harness with a terminal tool - thats what id O. But im so good/fast at pulling terminals it takes less time for me to do this than to pull out a jumper wire and figure which wire needs 5 volts to do what.
Bottom line is if you are getting a good crank sensor signal, and the reference signal going to the ECM is bad, the ICM is bad. Here it appears you are having failure of which signal? I cannot see very much here on your files. Is EST signal failing?
Also have you scopes the actual crank sensor or just REF hi? REF hi is the signal created from the crank sensor by the ICM.

The ICM is a common failure on GM vehicles, but it sometimes fails because of the coils, other times due to heat, and other times the ECM is not grounded properly. The ICM gets its ground from the ECM.

You should check out Toms creative lab scope technique page on the autonerdz home site. He goes over these failure quite thoroughly.

I would suspect the wiring first - check it for corrosion and do a wiggle test. (especially crank sensor wiring) Then look at the modules.
Maybe you can post some more waveforms that are a but bigger? I can barely see anything there.....

Finally what is the exact year, make/model vin/engine size? I can help you better if i know for sure
Right now I am guessing a bit on exact operation

You should get yourself a picoscope

Randy H. wrote on Sep 9^th, 2011 at 3:31pm:

Hard to follow you.  Extract EST with a terminal tool?  I "think" your saying get a 5V signal from elsewhere and put it on the Bypass wire?  At startup?  Can it start that way?  Break that down simpler for me.  Remember, this is the Non-Technician section, I'm a DIY but a retired machine repairman from Ford Motor.

Yes, the Bypass goes to zero, therfore the ICM pulls the EST zero and/or back to base timing and it stalls.

All I have for info is from AllDataDIY.  The diagrams only show two ground circuits or BLK/WHT wires, yet there are four that color on the ECM.  Voltage drop KOEO, the higest read 0.03V, well under the max allowed.

'90 Buick 3.3L VIN N.

I consdered a Pico years ago but the thought of needing a laptop on a stand with wheels didn't sound too good to me.  A Pico would be worth more than the car!

I'll post some bigger bigger pictures later tonight.  Not sure why you can't see the pictures well, maybe you need a better PC or maybe using a smarty phone?











Below is the EST, Bypass, 3X and 1x signals.

Mick wrote on Sep 9^th, 2011 at 8:17pm:

Mick:

Wait a minute!  Open the EST at the ICM?  Ah, isn't that going to make it stall for sure?  That's the spark timing going to the ICM which is what's happening now.  Don't you need the 5V Bypass signal to keep the EST high to control the ICM so the engine runs controlled by the ECM?

There is a Ref(Hi) and Ref(Low).  Not sure which you one you are refering to?  You want to check whatever Ref signal at the ECM, correct?  That way checking the wire?  All of my connections have been at the ICM so far.

I'm at the ICM seeing the EST, so it should be good.

What do you mean by, does it at this point kill the ECM?  Like fry it?

There was one day in the past, where it started, ran a few minutes and stalled.  I looked at some diagrams for thirty minutes.  It started right up and ran till the fan cycled On.  That was in the past and now, it doesn't start.

Retired wrote on Sep 9^th, 2011 at 8:59pm:


Retired wrote on Sep 9^th, 2011 at 4:19pm:


Please give us the complete serial number

I am having a hard time finding a 3.3L N engine with a distributor.

Retired wrote on Sep 10^th, 2011 at 6:55am:


First off do you have fuel pressure?

So this is the C(3)I DIS system with 3 separate coils mounted onto the module.

No sign of a distributor on this vehicle correct?

If I have it correct go to the ECM and connect your scope to D8 purple/white DREF and C8 white EST and an Amp clamp on C11 and C12 injectors and put time on the screen to see at least 2 engine cycles
Then zoom in on the injectors to verify for shorts.

You do have an Amp clamp right?

If we don’t have a signal on D8 we will work back from there.

Retired wrote on Sep 10^th, 2011 at 10:22am:


With not knowing the time scale on that screen I would have to guess that the engine was idleing slower than the othere screens.

Something you have to understand is that dref is buffered inside the ECM, that will give a delay in EST being produced.

Retired wrote on Sep 10^th, 2011 at 10:22am:


The fuse box is ok but you will need 2 fuse adapters.

Why have your scope leads all over the place when you can get what I asked for right from the front seat.

Retired wrote on Sep 10^th, 2011 at 12:15pm:


What is the voltage scale of that EST wave?

Are you saying those waves you put up are from it cranking no start?

If so let’s get RIGHT back to basics

Remove one sparkplug lead from a sparkplug and  insert a spark tester like a st125 or if you don’t have one of these get someone to crank the engine while you use a screw driver inserted into the end of the sparkplug boot and held quarter inch from the block, is there spark.

If this is too hard for you get your amp clamp and connect it to the pink wire of the ignition module are there primary pulses.


But just pull the ECM out and hook up to C11 and C12 of that connector and get injector pulses.

Retired wrote on Sep 10^th, 2011 at 6:55am:

Just a guess - like I said before I didnt know the make and model so i was making assumptions
And so you know whats listed in service manuals (theory of operation) isnt even accurate most of the time. I know this sounds disturbing but its the truth.

If the car doesnt start at all - you dont need the scope yet.


Get back to basics as Mick said - but i will add a few things he forgot to mention (micks a helluva technician - listen to him and pay attention)

******************
Check fuses and battery voltage FIRST!

smell exhaust after cranking and see if it gets gas

check ignition for spark with a spark tester as mick said (or use a timing light and see if it flashes, but this is not as effective)

If these check out check timing with a timing light in bypass mode while cranking
************
After doing these basic tests report back your findings so we can narrow things down

Note:
If you have a good scantool you can put the car in bypass by putting it in 'field service mode'


Always check basics first before scoping and jumping in head first - it will save you time and headache later:)


Sorry for the confusion - when you said HEI i assumed it was a distributor system. Since you are not a technician it is a little hard for me to follow you at times.

Now that I know the engine and vin we are dealing with it makes things much easier. Thanks for the info.

But bear with us and we will help you fix your car.

Retired wrote on Sep 10^th, 2011 at 1:22pm:


I don’t like that bypass being high and EST activated on cranking.

Will you capture a start up like the one I have attached here I want to see that the bypass is not shorted to power right from the start of Key on engine off to key on engine crank.

Does this engine sound as if it is cranking very fast like no compression or even worse an uneven compression.

Please do the injector capture.

you never did tell us if you are getting spark or if the exhaust smells like fuel when cranking. These are simple tests that dont take 2 minutes.

Retired wrote on Sep 10^th, 2011 at 5:07pm:


One black connector on the ecm has 32 holes you will find C 1, 2 and 3 are empty in one row just count from there across untill you get to C 11 and C 12 those dark green and dark blue are the injector trigger wires

The other black connector only has 24 holes.

Randy H. wrote on Sep 10^th, 2011 at 5:14pm:

Not yet as I'm by myself.  Now looking for my remote starter switch.  I don't recall any exhaust smells.

Mick wrote on Sep 10^th, 2011 at 6:23pm:

It's on the FPR schrader valve.  I was going to save Part II for later but here it comes!

During the week or so when it was starting I connected the gauge on the FPR, KOER I'd get 36psi which is within specs.  KOEO, by the time I get to the guage it showed 41psi.  I put a current clamp probe with another scope I have on the FP relay and get around 2A.  AllDataDIY states KOEO at 40-47psi, KOER at 3-10psi less with 3500rpm.

After reviewing my Current Ramping 1,2,3 from Linder Automotive,  I'm assuming that it has 8 commutator bars, it calculates to 3640rpm.  Sounds close enough.  I emailed them and Jim said more than likely eight bars.

Diagram shows FP Prime Test Lead which Jim mentions in his video but no loaction is given plus it shows two ORN wires and there's only one.  I find this red wire with a connector up near the firewall.  Red wire on FP relay to.

I go directly to the battery with scope/clamp.  I get 4A, 46psi at 2000rpm.  Thinking it might be the FP relay, checks fine on bench but that's just with a meter.  I jury rig the relay to use the other contact while directly to the battery but get the same 4A, etc.  Later I set a meter so I can see it when KOEO and I get the same 4A for that few seconds it runs then.

I can't find any reason for the current draw difference.  Possible bad ground with the extra load of engine, etc. running?  All grounds check good.

I also put vacuum on the FPR while connected directly to the battery and the current only dropped .5A.

The one time that it started and ran for about five minutes, I was watching the injector pulse width.  It was around 2-2.5ms, it just stopped like one turned it off, no roughness or anything.

Retired wrote on Sep 10^th, 2011 at 8:28pm:


I am not liking the saved parts that you are keeping from us I feel this is becoming a game and I am not into games.

If you could just give us the answers to what we ask it would speed this thread up as we have to get back to our own problems come Monday morning.

So it’s the answer to this

Mick wrote on Sep 10^th, 2011 at 6:23pm:


And this

Randy H. wrote on Sep 10^th, 2011 at 5:14pm:

That we need to know


Please don’t guess and please carry out the test on the fuel pressure gauge exactly like I asked.

So fuel pressure reads 0 on the gauge you turn the key on engine off and the fuel pressure rises to what pressure?

And is there spark?

Retired wrote on Sep 11^th, 2011 at 7:13am:


You crank the engine over yourself, then go to the back of the vehicle and smell the exhaust.

You dont have anyone around that cna crank the engine over for you while you check for spark?

And doing the fuel pressure as Mick asked is important.

If you cannot do these three tests exactly as we ask we cannot help you.

retired,

i'm just jumping in on this thread tonight (and am on my way to bed), but wanted to point out that your injector amp trace looks like you've got shorted injectors.  can you capture another inj amp with more closeup so we can see a more defined waveform?

EDIT:  well, maybe i'll take a better look tomorrow 'cause the inj volts capture don't look right either  .  goodnight

Randy H. wrote on Sep 16^th, 2011 at 6:05am:

Current or voltage?  I grabbed a voltage waveform right at one injector on the engine to verify the squarewave look with a Fluke 123 and got the same thing.  I grabbed but didn't save a current waveform at one injector with the Solarity.  It didn't have much slope and was real ragged looking.

The Solarity has some built in setups for testing different components and all you do is run them.  Ones for current limiting and non-limiting injectors.  They are triggered setups.  Tried both and neither triggered or captured anything.

Wouldn't a short show abnormally high current spike in the waveform?  What about the Bypass going ON/OFF during cranking?

It's a PITA to capture waveforms, take pictures, edit, upload and create a post.  OTC/SPX to this date has no scope that allows uploading to a PC for saving data or screens.  

The editor here is a bit funky when it comes to placing photos also.  The last two in the series above wouldn't go side by side as the others did for some strange reason.

I had to purchase another remote starter switch as a I couldn't find my old one.  I had to order the two different terminal tools from O'Reilly's.

jarvissamuel wrote on Sep 16^th, 2011 at 7:11am:

They are from a Solarity which I think if just the Genisys scope module alone.

Randy H. wrote on Sep 16^th, 2011 at 10:14am:

Here's some from a Fluke 199B 200MHz 2.5GS/s scope.  Lots of features but sometimes too sensitive.

Basically the same as the Solarity with better detail.  Notice how varied they are even when not zoomed in on.  Used the same 50ms time base as the last batch from the Solarity.

I was thinking about pressuring the rail by running the FP and then power them.  The pressure should drop.

Mick wrote on Sep 16^th, 2011 at 4:12pm:

Just turning the key to KOEO and OFF, the pressure goes to 46psi then drops to around 41psi.

I think that the injectors are supplied with 12V at KOEO.  I'm not following how that's going to check for pressure drop unless I ground the trigger side??  That also powers the ECM.

I was orginally thinking of doing it that way but thought, why power everything else too?

Checking for a pressure drop will answer one question I've thinking about.  Is it possible that the FPR could be blocking gas from the injectors?  It seemed to be working properly while it running but it's not even starting now.  I could power the FP from the test lead and use a vacuum pump but is that a 100% function test??

I also remember reading years ago about a way to test or compare injector banks.  You cross the two trigger wires and use a current clamp therefore having current flow in opposite directions.  If they are equal in theory, you'd read 0.0A.

You guys aren't commenting about the fact that the Bypass/EST are switching back and forth while cranking.  Or do I have more than one problem?

BTW: The Autonerz Creative Waveform requires some sort-of username and password to view.  Might need to be a Pico owner??

the Fluke is much better  - they make the best handheld scope on the planet IMHO - and we can see the details much better

these injector current waveforms are not showing any inductive reactance when they are turned on - it looks like they MAY be shorted internally if your scope has enough sample power in the timebase you chose. (10ms per divison as Mick said will allow us to get a better picture)

You may have more than one problem but lets repair what we know is broken first.

You should know that most scopes get weaker in longer timebases of 50ms and beyond, so you get less samples of the waveform. In other words, you may not get a TRUE representation of the waveform.
The Flukes are not like a Pico which performs great at 50,100,200ms and beyond.
However the Flukes do have isolated floating grounds which is freaking awesome.

Email Tom and ask him for the password to the creative labscope technique page. I think you may have to ask? You can also access the sample rate calculator there which will show you what I mean by the scope getting weaker sample power at long timebases.

Randy H. wrote on Sep 17^th, 2011 at 2:10am:

Your saying that they all are shorted?  Do they die of old age?  Remember there's only 20K on it.

Well, the Fluke Scopemeter line at least has software support.  They do have a new 4-channel model out now!

I must have had access years ago because I remember using a sample rate calculator.  I called OTC/SPX asking for a spec value to key into the calculator but they quized me on why I wanted it and refused.

I'm not sure if your familiar with Waveform Manager Pro from Metratek?  My first scope of any kind was the OTC Perception which is supported by their software.  The author was part of the Perception design team so he's known at OTC/SPX.  Years ago, he repeatedly approached them about supporting their Solarity with his software.  They jacked him around till he gave up!  

I actually have injector current ramp captures using the Perception from 2003 after replacing the ECM.  I should post one.

Mick wrote on Sep 17^th, 2011 at 6:24am:

It seems to crank evenly when cranked and no noise from the pulley.

This went from a return to me using Quick Start, two days later it start's right up and did that for a week.  A few times, it started, ran for a few minutes, just stopped, later restarted and to a no start.

I "might" be wrong but it seems that if it's shorted injectors, they wouldn't be a problem' go away and come back later.  Unless, they are/were partial shorts in the coil that have increased.

I'm in Warren, MI 48092, about a mile from the GM Tech Center.

That same injector pulser is at O'Reilly's for $135.99.

Quote:


No need for that.  Simply follow the directions on the page under the rolling eyeballs.  

The Fluke is miles ahead of the OTC but miles behind a Modis/Verus.  Pico is up to 700 times faster than a Modis so all the rest can't even be seen in the rear view mirror.  

Quote:


There are only two possible reasons they refuse.  

1. They don't know their own hardware (not good)
2. They are ashamed of it. (also not good)


BTW....I see the images Retired posted here reside on an outside server.  We prefer you attach them here so they reside on our server.  This preserves the integrity of the archives and prevents the images from later vanishment.   

Mick wrote on Sep 17^th, 2011 at 9:02am:

The time delay is whenever you post, add whenever I read one and getting/making time to perform the test.

Since your in Canada, do you remember a site there that provided training but also had a forum?  I can't think of the name right now although it's gone, I believe.  It was only for mechanics but I was allowed to post/ask questions because I had the Perception back in 2003.

BTW:  In my last batch of pictures in the Bypass waveform around 3-4V is a shinny spot.  That's the reflection of my bald head in the Solarity!  

Retired wrote on Sep 17^th, 2011 at 11:16am:


I understand what you are saying, but its not necessary to put one on wheels(cart).

Please let us know when you can do the injectors at 10ms per div.

Save this for later after you scope the injectors but:
Do you know how to check for excessive crankshaft end play?
(got a dial indicator?)

It is plain to me that there is a problem in the circuitry concerning the injectors; those highly irregular pulses.
   Questions like these come to mind...Is there a voltage drop on the power side of the circuit? Is the wire between the injector and the trigger intact, the connection solid?  Perhaps the fuse for it has corrosion? Does the power side have a loose connection?
It seems like it would be a bad connection on account of the intermittentness and irregular shape.

Mick wrote on Sep 18^th, 2011 at 6:11am:

That Canadian forum helped me use my Perception to find the problem on the same vehicle back in 2003.  Not sure if the URL is in my old laptop as I may have deleted it years ago.

I'm clamped on both trigger wires at the ECM as was asked for earlier.

I thought that a concrete answer as wether or not I have shorted injector(s) could be diagnosed without ohming individual injectors?

Since Tom aimed me at the way into the Creative Waveform page.  He has a voltage waveform for a shorted injector that is exactly what I have posted in Reply #40.

Yes, I have since ohm'd out the injectors.  Specs are 11.8-12.6 ohms.  I get 12.2, 12.2. 12.3, 12.3, 9.2 and the winner at 1.2 ohms.  The low ones are one on each bank.

I've read that ohming injectors isn't a 100% valid check but I'm unsure if that's true.  I was thinking of getting the injector pluser and using it to current ramp each but would that even be needed as it would be just a added expense but would be interesting?

Since injectors aren't cheap.  I've seen online from around $35-$60 and locally $60-$70 each.  Replacie just the two or all six which could be $300.  Remember, there might be other issues like the injector took out the ECM.  I've read this is a known issue on this engine.

Injectors, new, reman, brand name, etc.????????  Suggestions, please.

Mick wrote on Sep 18^th, 2011 at 7:14am:

What about my questions and sggestions?

Mick wrote on Sep 18^th, 2011 at 9:03am:

I cut my grass first, so it wouldn't bother me just in case it didn't start.  Just touched the starter and started like it always did!

I have a issue with the vacuum line going to the FPR.  It had a crack but it's odd, a short "S" shaped with 3/16" and 1/4" ID.  That's not a standard size at either end, each pipe a bit over standard size by about .015"-.020".  I had some 7/32" ID vacuum line, so I ran a 1/4" drill bit in one end of a short piece with a hose clamp on the small end.  The bend is too sharp and kinked.  The GM part is obsolete.  Any ideas?

A bit of additional question to ones asked earlier.  What's your procedure?  You scope, suspect a shorted injector.  Do you verify by ohming out or using a injector pulser?  If so, looking at pressure or individual current ramping with the scope again like I was thinking of doing?

Here's a capture with the Fluke and BTW looks pretty good on the Solarity too.  Don't see the pintel bump and it's got straight up start to it.  Just wondering if this is because of the one with 9.2 ohms, location of my clamp or something with the other supposedly good measuring ones??

I have captures taken in 2003 with the Perception that slope right from the baseline as they should and show the pintel bump but were taken right on the injector.

Looking forward to lots of good answers.

crackerclicker wrote on Sep 18^th, 2011 at 2:03pm:

No, that's why I mentioned the 9.2 ohm injector.

Yep, that was it, less current draw too.

There are butt splices for vacuum hose that will join two different size vacuum hoses. They are plastic junctions. Those are sold at common autoparts stores. Is there room to take an extra long piece of hose and bend it 360 degress in order to deal wih the kink? Also there are ninety degree junction/splices that would be different sizes.
They are vacuum hose fittings.

Retired wrote on Sep 18^th, 2011 at 10:58am:


How about I go for a week’s vacation before I answer your questions

Retired wrote on Sep 18^th, 2011 at 10:58am:



How about I thank you for a challenging post.

My son has a Sunday night hockey game I will be back.

Mick wrote on Sep 18^th, 2011 at 5:23pm:

It runs pretty good on only five cylinders but a lot rougher on four.

The site I spoke about from Canada would play these games.  A tech would have had a vehicle with a problem that they fixed.  They'd post the symptoms and ask what they'd want to check.  They'd post what was asked for and away it went.  Most used the Modis.

You play hockey in Canada?????  Nah!  

Retired wrote on Sep 18^th, 2011 at 6:47am:

Retired wrote on Sep 18^th, 2011 at 6:47am:


You are familiar with Linder tech so it would be in your best interest to give them call.
You make the call on whether the vehicle is worth the upgrade Bosch injectors, but I will insist you put a matched set no matter what.
http://www.lindertech.com/reconinj.htm

Mick wrote on Sep 18^th, 2011 at 7:49pm:

Called LTS this morning and they don't even have the cheaper Multec's for my vehicle, so I had to go with the Bosch DRI's.  They don't have/do my Multec's because of the frequent short outs.

The guy went on to say that the ECM will go out at 150K.  I told him that I had already replaced the ECM at 14K and it has only 20K on it now.  His response was, "Oh my!!".

What about your diagnostic procedure for injectors?  How do you verify them?  If it's OHMing only, what's the uses for a injector pulser?  LTS even mentions using one on their new injectors if they've been sitting on the shelve for a long time and they pulse their's before shipping.

Randy H. wrote on Sep 19^th, 2011 at 10:34am:


I did order a six pack of DRI's from LTS.

So do you use your OTC unit to verify a shorted injector?

What do you use for voltage drop test, the Pico?

Believe it or not I have a 5-Gas Analyzer and was going to use it maybe.  I found the software on my old laptop, installed it, powered it up to see what if anything was in memory and was greeted with the "Failed Calibration" and "Replace O2 Sensor".  The thing is old and no parts available but I "think" there are other units that use the same O2 sensor.

This vehicle has a ICM and ECM.  Now, since they are combined in the PCM and have been since OBD-II, aren't you more limited as to what can be done with a scope?  Don't you now a days need the systems used at dealers like the Ford IDS?  I have limited access to Ford's Oasis System and can look at all the manuals.  Every year the info has been reduced.  A big change came in 2006 in the Ford PC/ED manuals as they removed info concerning memory locations of PIDS .  My main ride is a '09 Ford Escape and there was some major changes in the PCM starting in that MY and even still to date there are several OBD-II devices that don't work correctly on it.

Randy H. wrote on Sep 18^th, 2011 at 5:56pm:


Thanks for the recognition Randy It’s nice to be appreciated now and then.

Retired wrote on Sep 18^th, 2011 at 7:47pm:


Absolutely not Bill
You see we use the Pico and both your scopes here just don’t cut it in our line of work.
Maybe ok for the DYI, what we did was to tell you how to use your scopes to the maximum capacity that those limited capacity scope could be used.
What I suggest you do if you want to tinker, is to purchase a quad kit from Tom and join in the Pico Group area were you will find all the techniques us guys use every day in our bays.
This is not the forum to give out this precious information.


Retired wrote on Sep 18^th, 2011 at 7:36pm:


When you buy the http://www.autonerdz.com/picoquad4000.htm you will find lots of this type of case studies, a lot of people learn from them, it’s a great way to share. So jump in and come drink the  

Mick wrote on Sep 19^th, 2011 at 5:23pm:

Mick:

Nope, a Pico is out of the question for me.  Maybe back in 2003 when I got interested in this stuff and chose a handheld over a laptop tethered Pico but I'm afraid it's too late for me now.

I'm a DIY in every catagory, speciality of none except when you get into mechanical stuff as that was my trade.  I was a Navy electronics tech but that was in the mid-sixties, so I'll say that I have an electrical background.

Pico could be the very best but I doubt if every shop has one.  Anybody in my area??  I asked above but wasn't answered.  Hasn't the advancements made in the automobile made through the years made the need for scopes, less and less?  The older manuals had waveforms, no such thing in newer manuals  which are thinner every year while explaining less and less also.  Hasn't this given way to the use of things like the Ford IDS which might have a built-in scope module?

Since the ICM is combined with the ECM, renamed the PCM under OBD-II and no published info about the PCM, aren't you left in the dark?  Or are the high end scanners that good.  I know that my ProSumer level scanner shows more PIDs on a 2004 Ford Taurus than my 2009 Ford Escape.

I breezed through some pages of other sections and didn't see much of anything about newer vehicles problems.  Lots of nineties vehicles but above two thousand, very few.

Retired wrote on Sep 19^th, 2011 at 7:57pm:


The need for scopes is actually more and more - you have that backwards. There used to be only a few wires in a vehicle - I can re-wire a 1970 Camaro in 1 day. But give me a 2010 Cadillac and there are MILES of wiring - it would take a month. The scope can help you narrow down problems in these miles of wire very quickly.

Who needs a book of waveforms? We have a LIBRARY of waveforms here on this site, and in the pico software, and we dont have to carry a book around!

Scantools have a sample rate of data, just like a scope - the less pids you have - the more samples it takes of data. There are a lot of things a scantool can miss - but the scanner can LEAD you to the right area quickly if you know what to look for.

I can see you have a lot of misconceptions about scopes and their use in the automotive field.
Just know this - there is a time to use a tool - and a time to put it away and use something else. Almost every technican I know of will ALMOST always pull out his/her scantool first, even when there are no codes. My Pico is pretty much my ace in the hole!

Retired wrote on Sep 20^th, 2011 at 6:32am:

I dont know what you mean by 'lack of posts on these vehicles'
remember you are logged in to the free access area - and you are not a member of picogroup. we have people post waveforms almost every day of every type of car you could imagine.
But you have to buy a scope from tom to participate in that section.
sorry.............

Randy H. wrote on Sep 20^th, 2011 at 8:46am:


Tom does offer unlimited access to the Autonerdz support system for an annual fee.

You can read about it here:
http://www.autonerdz.com/picokit.htm#_Plus_you_get

HTH

dave

crackerclicker wrote on Sep 20^th, 2011 at 5:07pm:

crackerclicker wrote on Sep 20^th, 2011 at 5:07pm:


+2

To answer the one we missed:

If the electrical connector is sealed (weatherpack, metripack, micropack, etc.) dielectric is not necessary. You really only need that on your battery cables and plug wires. NEVER use it on HO2S wiring unless you want to buy another.

Geez you have a lot of questions Retired. 

Just joking with ya

resistance changes as a coil heats up and cools down
and also the short may be changing its resistance some due to gasoline inside the injector. Hydrocarbon is a conductor.

Retired wrote on Sep 21^st, 2011 at 4:50am:

what were you talking about then?

I received the DRIs from LTS today.

I OHM'd them all out but was very suprised to see one with sharp pointed top edge of the connector at one corner rolled over with large burrs.  I was doubting if the connector would go on, so I scraped them down a bit with a three-corner scraper and tried a connector.

Half of them had a white residue on the contacts.

I found the single sheet of instructions for the upper retaining clip somewhat confusing, so I called LTS.  I ended up talking to Jim Linder who explained what they were trying to say.  Why not just say that the Multec has one retaining groove but the DRI has two, use the top groove.

I mentioned the connector which he suggested was a UPS problem.  No hole in the box, bubble wrap or ZipLoc bag, so I doubt it.

He said that they wire brush the contacts and couldn't understand why I received ones with dirty contacts.  He said that they use dielectric grease on every injector replacement job they do.

fisher wrote on Sep 22^nd, 2011 at 7:57pm:

Every wire has a beginning and an end where the bare copper is exposed to some degreee.

Granted, a cars engine bay is usually much less corrosive than a salt atmosphere; the difference is obvious when you see it.
     The Idle Air Control valve is radical to control of the idle speed, period. If it has a zillion miles on it you could say there is no need to diagnose anything as natural circumstances are bound to wear it out.
I'll bet if you replace it with a GM part and per chance a PCV valve and PCV hose - GM of course - that you would find a difference...providing of course you haven't done that. It sounds like it is upon it's golden hour as a vehicle and a few dollars spent will give it a new lease on life.
The dielectric is an insulator and in the case of use on ignition modules - the thick film on the back of the module provides a heat sink; aborbs and dissipates heat so that you dont leave that for the transistor to do; then using a dielectric so that we can avoid transmitting or drawing power with our heatsink grease...