'02 3500 360gas intermittent loss of spark

[jimm]

2002 360 gas 3500 w/80K miles on it

drove it 10 mintutes to town, ran great. Parked and come outta store 5 minutes later and would'nt start. Turned over great but no spark. Then after 5 tries in 5 minutes it finally started and I made it 4 minutes down the road and it stalled again. Then got it goin after a few tries and made it another 4 minutes down the road then towed it home.

Then after the course of a month i would test run it in driveway and it would usually run a half hour to an hour then shut down, a few times ran a whole 2 hours before quiting just sitting still idling. I tried gently wiggling the wiring harness and connections as it ran but nothing helped. I put a new coil in it but made no difference. Bought me an OBD2 and no codes showed.

Finally drove it down to shop for a professional fix. He put it on his $140.- "Engine Performance Ignition System Analyzer" and it showed NO codes. So he first replaced the "camshaft positioning sensor" and it did'nt help

Next new part was the "crankshaft positioning sensor" which did nothing to help either

Now his next step is to replace the pewter which is 8 hundred bucks but if that fixes it I'll be happy happy


he (and myself) think it's probly not in the wiring harness as it sits motionless idling for up to 2 hours without quiting so probably not a broken wire as the engine doesnt shake at all when idling
******************************************************************
Any tips on what else may be checked before I waste 800 bucks on a new pewter if i don't need one

I'm lost and so is he cause his bigdik spendy analyzer machine don't say nuthin. Usually lately now right after it quits it will start right back up so it's hard to troubleshoot when it's not actively broke

He is an old school good mechanic and very trustworthy so I'm happy about that part but need my truck fixed. Now it's sitting behind the shop while other rigs that came in after mine are getting fixed.

Maybe if somebody has a tip on an overlooked common problem with these rigs I could go down there and fix it myself or point it out to the shop.

Any help is greatly appreciated

 

[jimm]

no ideas?

I just checked with dodge dealer, since stelantis took over dodge is terrible at supporting products they make

My mechanic said next step to throw more parts at my problem is a new pewter and dodge dealer says they don't make em anymore

Can anybodyt tell me a good aftermarket brand please?

 

[jimm]

breaker break break on 19 please for some information

anybody gots their ears on

 

[Daw14]

Coil

 

[Sherman Bird]

2002 360 gas 3500 w/80K miles on it

drove it 10 mintutes to town, ran great. Parked and come outta store 5 minutes later and would'nt start. Turned over great but no spark. Then after 5 tries in 5 minutes it finally started and I made it 4 minutes down the road and it stalled again. Then got it goin after a few tries and made it another 4 minutes down the road then towed it home.

Then after the course of a month i would test run it in driveway and it would usually run a half hour to an hour then shut down, a few times ran a whole 2 hours before quiting just sitting still idling. I tried gently wiggling the wiring harness and connections as it ran but nothing helped. I put a new coil in it but made no difference. Bought me an OBD2 and no codes showed.

Finally drove it down to shop for a professional fix. He put it on his $140.- "Engine Performance Ignition System Analyzer" and it showed NO codes. So he first replaced the "camshaft positioning sensor" and it did'nt help

Next new part was the "crankshaft positioning sensor" which did nothing to help either

Now his next step is to replace the pewter which is 8 hundred bucks but if that fixes it I'll be happy happy


he (and myself) think it's probly not in the wiring harness as it sits motionless idling for up to 2 hours without quiting so probably not a broken wire as the engine doesnt shake at all when idling
******************************************************************
Any tips on what else may be checked before I waste 800 bucks on a new pewter if i don't need one

I'm lost and so is he cause his bigdik spendy analyzer machine don't say nuthin. Usually lately now right after it quits it will start right back up so it's hard to troubleshoot when it's not actively broke

He is an old school good mechanic and very trustworthy so I'm happy about that part but need my truck fixed. Now it's sitting behind the shop while other rigs that came in after mine are getting fixed.

Maybe if somebody has a tip on an overlooked common problem with these rigs I could go down there and fix it myself or point it out to the shop.

Any help is greatly appreciated

You need a new mechanic. Anyone who depends upon DTC's to "tell" them what to fix is unqualified, period, end of discussion. There are numerous rabbit trails to venture down to accurately find the problem.

Next diagnostic tool to get out is a DSO (digital storage oscilloscope). On THAT particular vehicle, I'm going to look at patterns for secondary ignition, paying particular attention to the dominating spark gap, FIRST (either the distributor or the spark plug) This is almost ALWAYS overlooked by so-called diagnosticians)

I'm going to put a 600 amp inductive pickup on the negative battery cable, and, while the engine WILL run, observe phantom phase secondary ignition electro magnetic bleed-over.

Somewhere in this journey, I'm going to get a scope pattern of the fuel pump inductive signature.

In all of this, I'm going to look for voltage drop across both the positive and negative circuits of the engine management system.

There are many more tests that I can mention here, but I DAMNED sure am NOT going to throw an expensive ECM, PCM, or whatever nomenclature is germane to this particular vehicle. Not yet, by a long shot!

 

[Sherman Bird]

no ideas?

I just checked with dodge dealer, since stelantis took over dodge is terrible at supporting products they make

My mechanic said next step to throw more parts at my problem is a new pewter and dodge dealer says they don't make em anymore

Can anybodyt tell me a good aftermarket brand please?

IF, and I emphasize IF, you do need the computer rebuilt or replaced, I use NPC here in Houston, and have been using them for 22+ years. I've gotten stellar results on the rare occasions that the engine management computers HAVE been replaced. npcautomotive.com or 866-366-4227

 

[Yeret]

By chance, when the engine won't start up, does "noBus" appear in place of the odometer? "noBus" means that the gauge cluster is getting no communication with the ECU, but won't necessarily prevent the engine from running. Been there, done that, but that's not really relevant here.

However, should the engine fail to start in addition to "noBus," that means either the ECU is either not functioning, or there's a bad connection somewhere. In the case of the former, the most probable causes is a bad solder connection somewhere in the ECU, which is certainly fixable, but you gotta find where the bad connection is, LOL. In the case of the latter, your best to start looking through grounds; they need to be clean and tight.

Issues with the ECU will sometimes generate a code, but not always.

 

[Tominator223]

Not sure if it has a secondary pick up in distributor , that could be one issue. I’ve used a ground wire from ecm to battery ground before to find a ground fault. On more than 1 vehicle ,and left it without issue . Also it could be a security issue where the anti theft shutting it off.

 

[Sherman Bird]

Not sure if it has a secondary pick up in distributor , that could be one issue. I’ve used a ground wire from ecm to battery ground before to find a ground fault. On more than 1 vehicle ,and left it without issue . Also it could be a security issue where the anti theft shutting it off.

Nope! the Crankshaft position sensor on top of the passenger side of the trans bell housing is where spark toggle is for this truck. They are known failure items, but aftermarket are pure garbage. That doesn't mean to just throw one at it. Diagnosis is a must!

 

[Dusty]

You need a new mechanic. Anyone who depends upon DTC's to "tell" them what to fix is unqualified, period, end of discussion. There are numerous rabbit trails to venture down to accurately find the problem.

Next diagnostic tool to get out is a DSO (digital storage oscilloscope). On THAT particular vehicle, I'm going to look at patterns for secondary ignition, paying particular attention to the dominating spark gap, FIRST (either the distributor or the spark plug) This is almost ALWAYS overlooked by so-called diagnosticians)

I'm going to put a 600 amp inductive pickup on the negative battery cable, and, while the engine WILL run, observe phantom phase secondary ignition electro magnetic bleed-over.

Somewhere in this journey, I'm going to get a scope pattern of the fuel pump inductive signature.

In all of this, I'm going to look for voltage drop across both the positive and negative circuits of the engine management system.

There are many more tests that I can mention here, but I DAMNED sure am NOT going to throw an expensive ECM, PCM, or whatever nomenclature is germane to this particular vehicle. Not yet, by a long shot!

Sounds like his $140 tool just brought him to the next level of shotgunning.

Regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33-gallon fuel tank, 18” wheels. Build Date: 3 June 2018. Now at 123560 miles.