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93 F150 won't start (Read 5,898 times)
istk
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93 F150 won't start
May 26th, 2004 at 2:21pm
 
tried self diagnostic and get a 12v reading on
all terminal connections ?

Bad PCM or EEC-IV ?

The manual only tells what to do with trouble codes.
I can't get any.

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neil-ca
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Re: 93 F150 won't start
Reply #1 - May 26th, 2004 at 10:31pm
 
Hello istk,

An engine needs fuel, ignition and compression to run. Start your diagnostic test by finding out which of these things are missing. Don't worry about computers or codes till you know what direction you are going.

If you don't know how to check these three things you might be smart to find a good shop with people you can TRUST.  I know it seems expensive to have to pay someone to check the truck out, but I see people spend  tons of money on parts they don't need.

If you want help doin it yourself you'll have to supply a little more information .

You should be able to "pull codes"  on that truck with a paperclip  Wink
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istk
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Re: 93 F150 won't start
Reply #2 - May 27th, 2004 at 8:59am
 
Have all three, plus new Dist. cap, rotor and wires.
The quality of spark may be in question.
I ground a plug and it fires, how good I don't know.

I need the next level.

Tried jumper on SIT, with volt meter and get 12 volts
all the time no dash output. I don't believe this to be right.
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neil-ca
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Re: 93 F150 won't start
Reply #3 - May 27th, 2004 at 8:42pm
 
If you have all three then the engine should start.  A spark tester would let you be sure that  secondary voltage is sufficent to fire.

I wonder how you know you have fuel?

Compression can be tricky somtimes. When you say "compression is good" you mean that the engine has no mechanical problems. Piston rings , timing chain, valves, gaskets can alll come into play.

If you towed your truck into me I would ask a couple of questions.

1. When was the last time the truck was running?

2. What happened? (were you driving it and it just quit? Or did it just not start after being parked)

3. What happens when you turn the key? Does it sound normal when it turns over? Do you hear relays clicking and stuff happening when you turn the key on? Does the "check engine" light EVER light up?

4. What sort of work has been done on the truck in the last month or so. This means anything, battery or cables, stereo, alarm system, engine mods, anything!

The answers to these questions would lead me to a plan for testing. I might check the fuel pressure or ensure the quality of the spark was sufficent. I might run a compression test or make sure the distributor and plug wires were indexed properly.

I would certianly have  a good visual inspection under the hood. It's suprising somtimes how these deeply technicial problems can turn out to be somthing so simple you want to kick your own rearend for missing the obvious. Happens to the best of us.

I'll say it again, if you find a reputable shop to do business with it can save you much money and much time. try this link here.

http://www.iatn.net/dir/search.asp

There is no "next level" it's all a process. Being there can make all the difference in the world to an experienced tech.

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Doug S.
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Re: 93 F150 won't start
Reply #4 - May 27th, 2004 at 9:54pm
 
Hi ISTK,
If I could ask, when you connect a DVOM red test lead to the red wire at the idle air control and the black test lead to ground with the key in the run position, what do you get?  It should be very close to battery voltage.  This can be a quick test of the EEC power relay.  If that isn't working properly, you won't get fuel and may or may not even have spark.  This is one of a few quick checks that can be made.  I hope this helps  Smiley
Doug S.  (aka Ziggee)
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