This is a long story and I will try not to be long winded. This really started long before I became a member here and before my ECM crapped out so bare with me.. About 6 years after buying the truck my ECT just fell out. Very typical of a failed t stat. Thru the years and many t stats plus a couple sensors and radiator caps, most recently replaced them all again three weeks ago.Even sent one to @Mopar1973Man packed in one dollars and it worked fine for him. After installing a cheap Suncoast gauge from Auto Zone under the hood and it mostly told the engine temp was good. Something in the wiring. I hate wiring.

 

About three years ago I started experiencing some surging in the engine, at idle and you could feel it under light throttle. It would pop some APPS codes during these episodes. Occasionally it would rev up to near 10% and pop a 0222 code and go to a dead pedal. I would have to pull off the road and wait for the pedal to come back. I did some diagnostics and it all pointed to the APPS. Had a Timbo and just did not want to buy another without knowing for sure. So I bought a cheapy off ebay for 16 bucks. Installed it and sure enough no surging. So I bit the bullet and bought a new Timbo. Put it on and every thing was good for about 5 minutes and the surging was back. I put the cheapie back on and no surging, but soon after it popped a 0222 code but still drove just fine. Cleared the code many times but always came back as soon as I started the engine. I got worried about it and put the Timbo back in and learned to live with it. Not the best way to handle for sure but it is what I did. 

 

Fast forward to about 4 months ago and all this started getting out hand. My engine temp was down to levels I have never seen. A few times I watched it drop from 170 to 135 on the scan gauge at the snap of finger. Surging was getting worse and the cruise was going wacky. Some days the surging was crazy and it would pop the 222 code, dead pedal, and then the cruise would not turn on until the engine would surge again. Just whacky behavior. The engine was throwing codes and the 4 seem to repeat themselves. 236, 237, 121, 222. The 236 seemed to be the first one of the 4 to pop. Not sure why but that how it was happening. I remember posting about this before and IIRC @Mopar1973Man said something to me about checking the MAP sensor harness or sensor not sure which now. But I did still have my OE MAP sensor from when the ECM crapped out on me so I figure I would put it in one day and see what would happen.

 

Fast forward to today. I figured I would stick that MAP sensor in before heading back to Maryland. Pretty simple right. Well when backing the new one out I dropped the socket with the sensor in it and never heard it hit the ground. Should not be a problem beings it was a 1 1/16" deepwell socket with a sensor sticking out of it. It fell back in behind the starter and took me 30 minutes to find it. Not to mention its about 98* outside and 85% humidity and I am sweating like pig but did finally find it. Installed the old one and while trying to plug the harness on I broke the connector off of the MAP sensor. Guess it got brittle over the years who knows. Any way I put the old one back in and I am soaked in sweat and tired of F'ing with it all.

  

I just drove 450 miles with no surging and temp gauge that read normal all the way up here. It swung between 190 and 195 the whole way. I have not seen that on my dash in 10 years. I am amazed but not sure how the MAP and the ECT are interconnected at the MAP harness.

 

Anyway I am as happy as a mule eating briers but figure this will come back one day and need to figure out how this happened.

 

Any thoughts are appreciated. So much for no long windedness but if I had told the whole story I would still be type for another hour.

 

Edited July 24, 20177 yr by dripley

Wow... All i can say is Wow!

  On 7/24/2017 at 4:35 AM, Mopar1973Man said:

Wow... All i can say is Wow!

I am a little stunned myself. One part I left out. I put some DAP 50's in the truck a few months ago and they were smokey. When this last bout of surging and codes was happening I noticed that sometimes they were not smokey and other times they were but never got correlation of what was happening when they were or were not. Other that haze at WOT they dd not smoke coming up here and I hammered a few times to make them smoke. Did not even smoke when lugging the engine.  

Edited July 24, 20177 yr by dripley

That is great to hear and am so glad you got rid of the surging.  I know it's been bugging you.  Amazing that something that seems so unconnected to a problem can actually be the problem.

 

L8tr

D

Did you check for 5v on map and oil pressure sensor, I believe there are others that may share the loop. I've heard of oil pressure sensor grounding out when oil gets in there and causes everything else in loop to mulfunction. 

They are all tied together on the ground. Would not be a bad idea to locate the splice and make sure no greeny crusties are there.

  On 7/24/2017 at 1:41 PM, Dieselfuture said:

Did you check for 5v on map and oil pressure sensor, I believe there are others that may share the loop. I've heard of oil pressure sensor grounding out when oil gets in there and causes everything else in loop to mulfunction. 

I did not any signal voltage on anything. Did not have the time. I figured to just change out the sensor and see if it might be flakey. Think I proved it is not the sensor; Last week I pulled the same connections loose and cleaned them up and nothing changed. The sensor seemed to be the next logical step. I did have my hands shoved in the ECM  wiring and whatever else was down there while searching for the socket I dropped.

 

  On 7/24/2017 at 2:06 PM, jlbayes said:

They are all tied together on the ground. Would not be a bad idea to locate the splice and make sure no greeny crusties are there.

Would that be the one that is buried in the engine wiring harness?

More than likely. I have not looked up its location yet. Just the diagrams on here showing the commonality between everything.

Just looked....no location given...FACK.

If you haven't changed oil pressure sensor, I would change it out just to be safe, it can leak internally. I know most will say don't change parts for no reason. Up to you. Definitely check your 5v loop and ground when you find it.

  On 7/24/2017 at 3:02 PM, jlbayes said:

More than likely. I have not looked up its location yet. Just the diagrams on here showing the commonality between everything.

Just looked....no location given...FACK.

I believe you are speaking of S165. The wiring diagram shows a splice near the breakout for the ECM. Another fun place to stick my hands into. But I did have my hand shoved down in there searching for the socket. A good a place to start as any.

 

  On 7/24/2017 at 3:48 PM, Dieselfuture said:

If you haven't changed oil pressure sensor, I would change it out just to be safe, it can leak internally. I know most will say don't change parts for no reason. Up to you. Definitely check your 5v loop and ground when you find it.

I am thinking more of the wiring than the sensor. But they are not near as pricey as a MAP sensor. Thats why I was trying my old one. Still cant believe I broke it. Gorilla hands I guess.

 

Anyway all functioned as normal today in my driving around Maryland.

I left off another important lesson learned with this work I did, Be sure all of your tools are out from under the hood before closing. Had everything put up, closed the hood and walked to the house. Thats when I noticed I did not have my glasses on. It is amazing how much you can bend a pair of glasses when you lay them just above the rubber on the cowl and slam the hood twice. Damn!!!

I know all about that stuff I have to think about everything I do when putting something down.

 

Forgot where I put something so go look around meanwhile I put down what I didn't forget and then freaking loose that too. I hate that drives me nuts.

I can't see without my glasses so I seldom take them off. Of course if I did I would lose them

I don't know how many times I've dropped tools between the radiator & intercooler. Talk about trying someone's patients.  How many times I've left stuff under the hood... only god knows.

 

L8tr

D

  On 7/26/2017 at 4:25 AM, JAG1 said:

I know all about that stuff I have to think about everything I do when putting something down.

 

Forgot where I put something so go look around meanwhile I put down what I didn't forget and then freaking loose that too. I hate that drives me nuts.

Sounds like a classic example of CRS disease, fairy common in the aging process. I am showing symptoms of it myself,but you don't need to seek medical attention because thier is no cure.

 

C. (can't)  R.(remember)  S.(....it).  

  On 7/26/2017 at 4:40 AM, Royal Squire said:

I can't see without my glasses so I seldom take them off. Of course if I did I would lose them

I had the lens in my left eye replaced some years ago and now working under the hood is right in my best vision zone. Easy to work above the engine with them off. I only notice it when I am walking away.

  On 7/26/2017 at 11:09 AM, SilverMoose said:

I don't know how many times I've dropped tools between the radiator & intercooler. Talk about trying someone's patients.  How many times I've left stuff under the hood... only god knows.

 

L8tr

D

Two words for that one. Telescopic magnets. I would have no air flow if it was not for that simple tool.

  On 7/26/2017 at 12:30 PM, dripley said:

Two words for that one. Telescopic magnets. I would have no air flow if it was not for that simple tool.

 

YEEEPPPPP. SOL when messing with anything stainless or aluminum though lol

  On 7/26/2017 at 1:04 PM, jlbayes said:

 

YEEEPPPPP. SOL when messing with anything stainless or aluminum though lol

Tie wire is good for tool fishing.... bends easy and stays formed the shape you need to hook tool.

 

I think Dripley is only guy with tie wire in his truck.

Edited July 26, 20177 yr by JAG1

  On 7/26/2017 at 1:44 PM, JAG1 said:

Tie wire is good for tool fishing.... bends easy and stays formed the shape you need to hook tool.

 

I think Dripley is only guy with tie wire in his truck.

 

Have a roll of it on a peg in the shop lol

  On 7/26/2017 at 1:53 PM, jlbayes said:

 

Have a roll of it on a peg in the shop lol

Same here I've got 4 rolls...

 

Tie wire is handy you can make all kinds of tools with it. Like probe tips for electrical sockets, small snap ring tips can be made. List goes on and on.

  On 7/26/2017 at 1:04 PM, jlbayes said:

 

YEEEPPPPP. SOL when messing with anything stainless or aluminum though lol

That's very true. But I do have a couple of those spring loaded grabber thingy's for just such a situation. Most of my stuff is just cheap iron though.

  On 7/26/2017 at 1:44 PM, JAG1 said:

Tie wire is good for tool fishing.... bends easy and stays formed the shape you need to hook tool.

 

I think Dripley is only guy with tie wire in his truck.

Unfortunately the only tie wire I ever seem to have in the truck is those little 6" loop ties. Cant grab much with those little things. Do have a roll at the house. It is good stuff.