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https://www.autonerdz.com/cgi/yabb2/YaBB.pl General Public Area >> PicoScope >> Chrysler CMP/CKP https://www.autonerdz.com/cgi/yabb2/YaBB.pl?num=1077639086 Message started by Misfire on Feb 24^th, 2004 at 8:11am

Title: Chrysler CMP/CKP
Post by Misfire on Feb 24^th, 2004 at 8:11am

I am having trouble finding a "good" reference for a 95 Dodge Intrepid 3.5 CMP/CKP signal. Am I 1 tooth off here? Can anyone help? Unfortunately cruise ctrl bulb evidently burned out.( It will supposedly flash when cmp/ckp signal off on this engine) Low vacuum (13" at idle) causing map to tell PCM dump extreme amount of fuel, Cherry Red Cat. OK, restricted Cat or CMP/CKP sync off ?, as Shakespeare said, "that is the question". Have the car for a few days, Anybody got a "good" wave? Thanks,
Misfire
http://www.autonerdz.com/images/jt1.jpg

Title: Re: Chrysler CMP/CKP
Post by Tom Roberts on Feb 24^th, 2004 at 8:56am

Hi Misfire,

Your capture is out of sync. The PCM usually has no clue when the CMP/CKP relationship is out of sync. No flashing bulb or scan data parameter is reliable. You have approached this in the only way to confirm this reliably...with a scope. (other than dissasembly)

Here is a one second capture of 12 engine revolutions of this relationship:

Now let's zoom in x5 and overlay them:

As you can see, this one is different than your relationship. Who knows how far off the other cam is, but that one is certainly off. :o

Title: Re: Chrysler CMP/CKP
Post by Carl Grotti on Feb 24^th, 2004 at 11:41am

Misfire,

I had one that was off by 1 tooth and it looks the same as yours. The RH sprocket was off by nine teeth. Be nice if they would put a CMP sensor in that bank to. :-/

Carl

Title: Re: Chrysler CMP/CKP
Post by Misfire on Feb 27^th, 2004 at 9:29am

Pulled the timing covers off today and sure enough belt had jumped 1 tooth bank 2 cam sprocket. Hard to believe 1 tooth would make it run as poorly as it did. Belt has a chunk out of it, just repositioned it for now and started engine to assess how it would run. The customer want's to repair this 225k car despite my telling him I have no earthly idea what made the belt jump. We replaced the water pump idler, tensioner and belt 1 1/2 years ago and all except the belt are fine now. Checked for a cracked flex plate which is a common problem on these engines but this one looks ok. Makes me nervous but I guess I'll put a new belt on and drive it. Only thing I can think of was one heck of a backfire. Anybody seen anything similiar?
Thanks all, oh by the way before I pulled it down this am when I pulled it in the cruise light was flashing so I guess the other reports I have seen are true about the cruise light flashing when ckp/cmp sync are out.