Another Idea occurs to me. I had forgotten I did this, I took it in to make sure all the PCM updates were in order. They told me it was but the same guys fixed the thing after the trans rebuild and said they didn't. Anyway you might find out if you have all the updates on your PCM.

 

I am assuming when you are talking about updates, your talking about something dealer related? CLosest dealer is about 80 miles away and this thing wont even make it to the next street. And though more modern ability to present different PCM features to a scanner might would be the outcome, I dont see where an update should have anything to do with the way its running, or in my case the lack of ability to run right.


It looks like I am at the point of ringing out each and every wire coming out of the PCM to wherever it goes. After about $1200 in parts this thing is not running much different than it was the day I got it. It is down to a point that its either a broken or intermittent signal wire or the PCM itself.

 

I was thinking it was driveable. Yes I am referring to dealer updates to the PCM programming. Can you post a recording of the motor running and backfiring sound?

 

Driveable?....maybe 100 yds one time at 5mph max, next time it will buzz down the hghwy at 60+ until you let off the throttle, then all you get is to the floor 5mph. Im headed out of town tomorrow and not back until Labor day weekend. Can maybe do a video then. My next plan is a wire by wire testing, Just dont have any time for that until I get back.

 

Back at this nightmare...have been traveling either business or pleasure for near a month.


MY last attempts were to check ALL wires in the harnes going back to the ecm for all engine bay components. I found no wires to be an issue but did come to the conclusion that I had 2 injectors that were not getting a fire signal from the ecm. I sent the ECM out for repair. They mentioned that several solder connections were infact broken internally, but that after rep[air all is ok. It returned earlier this week, Installed and does run better. The backfiring/popping is mostly gone but still slightly there. BUT, Initial placing of foot on accelerator still creates a bogging down/ stalling then all of a sudden take off as it should. I ran it down the highway at 70 the other day for up to ten miles and does fine if already moving and easing intop the throttle, but any heavy pedal action only results in loss of power. Will now rev up properly IF and only if you ease into the accleration very slowly. To push the pedal in a normal or heavy approach only gets you a bogdown or stalling. Wondering now if maybe it may not be injector related? I Put a can of seafoam in it yesterday and ran it just a little bit aroun the yard to get it shaken up in the tank and moving through the fuel system. Will do some more runnign this weekend.


I have no doubt a very tiny bit of not perfect running might be due to the injector syncronization, as the distributor had been moved and I have no way of 100% synching it without obtaining the special scanner by which to do so. As Ive moved the dizzy various amounts around visual recommendedp FSM pickup coil settings (while running and attemting to rev while doing so) and seen very little effect in making this Bogging/stalling situation better, I see no reason to obtain a scantool for 100% accuracy of that setting at this point. Only thing under the hood at this point that has not been replaced or dealt with is the injectors themselves. Sending out for cleaning is about as costly as just replacing. Would still like to make time to do a small video as requested by one here, but just have not had the time.

 

I don't remember all you have done here. I was thinking TPS and throttle Valve cable after your description in this last post. I would make sure the cable is set at the trans then at the TB. https://dodgeforum.com/forum/1st-gen...djustment.html
Fuel Syncing will make a difference but I can't say for sure a bad setting would cause your problem. If you looked down over it to align the marks with the motor at TDC You are most likely within spec as long as it didn't move while you tightened it. I had mine set visually and when I sprang for the MT2500 it turned out it was bouncing between -6 and -15. I got it to sit stable around +1 when I used the scanner after messing with it for 20 minutes.

 

If you looked down over it to align the marks with the motor at TDC You are most likely within spec as long as it didn't move while you tightened it.
Agree, and at the moment with the tweaking IVe done to make sure that is not the issue, going back to baseline visual I DO need to check and just leave it there unless I were to have the snapon or similar tool.

 

Thisis where this stands to date.

STILL,when throttle is applied is just bogs down, but on occasion will rev upproperly (but only when warm). Noticed that when cold does not appear to be ina revved up choke condition also. Trying to rev at all during cold/warmup istotally useless.
Everyitem in the ignition system is new. Plugs, wires ,cap, rotor , Ignition coil.All were 20 years old and original.


Every sensor has been replaced.


Every wire from every sensor has been tested for continuity both back to the ECM, andall grounding ckts. All power wires from battery out (those weird plugs) hasbeen checked, cleaned, and dielectric grease applied to prevent any future corrosion.


O2, was bad, TPS was unable to test good or bad butreplaced. MAP would not testproperly so replaced. Crank sensorreplaced but found not to be bad. Distributorpickup coil (cam sensor) replaced but believe to not have been bad. IAT tested bad so replaced. IAC motor was replaced as it was frozenup. Coolant temp replaced due toexternal damage. ECM was sent outfor repair as two injectors would not fire, they now all do. ALL injectors replaced.


Internally,the Timing chain set with new tensioner was replaced due to being worn out.Plenum gasket was blown so replaced with hughes kit.
Fuelsystem filter replaced and several times testing of fuel pressure done both atidle and at near full throttle, holds a pretty consistent 40psi.


Exhaust system CAT pulled to confirm no possible clogging.


Compressionchecked several times on both a cold and warm engine. All are within just a fewpsi and all are in the 160-170 range.


The only thing under the hood that pertains to fuel, firing or ECM feedback is the a ctual metal butterfly part of the throttle body. But have inspected numerous times.Nothing is cracked, no slack or looseness in the butterfly shaft. There is nothing else on that which could be bad, it basically a metal block with a butterfly and a shaft. (TPS & MAP,IAC all new as stated above)


The distributor itself has never been pulled, but has been moved about slightly totry and by eye get the injector synch better to maybe help solve this bogging issue. When adjusting while engine running I see very little effect inrunability unless I take it too far in either direction then, just like atiming too far out I will tend to get a backfire or valve chattering typecondition. Ive got that back in the best run state but still this bogging downon throttle position movement exists.


I can manage to get it going down the road as long as I keep the rpms up but when it comes to a hill, the gentle feathering of the throttle will not keep up with the hills demand for power. To push the throttle harder only results in abogging down and loss of power.


I have never in all my years of working on cars ever seen a vehicle act this way that changing a TPS or MAP would not fix. Still trying to get a video attached,but my only attempt ended in a vid saved in a certain format that only my phone would recognize.


Open for any and ALL suggestinos or ideas that is does not appear I have mentioned.

 

Can you set up a gauge to watch the fuel pressure as you drive particularly when it bogs?

 

IVe done that it holds around 40psi entire time.

It can be at idle and attempt to open the butterfly and it does the same thing. Gonna try and get a video. First day off in 14 so playing catchup around the house.