Anyone got a link to an existing ECU thread? I'm sure there is a great one here somewhere...

Glitches with the Engine Control Unit (ECU) in 90's Dodges seem to be more common then we would like to see.

I have had a faulty fuel sending signal within the ECU on my 1995 v6 3.5L in the past. My transmission started jumping and I wasted time with filters and pumps before narrowing the cause down to the ECU.

NOW I have a clicking fuel relay issue. You can follow the full blog of all my experiences with the v6 3.5L at http://freehelpinghands.wordpress.co...995-6l-repair-

My ticking relay behind the driver firewall is the fuel pump relay. My blog has links to all manuals and diagrams. My pump relay is slow to engage due to voltage but I am still testing options to identify if it the ECU or a recent ground. I'm going through the wiring, trying a battery charger while starting and looking for a loner ECU to swap out for a second as of April 2014.

I look forward to ECU talk links to help me and my readers learn more about known ECU issues.

 

had to replace the ECU in my 92 B250 after numerous stalls and no starts--less than $100 at auto zone 3 yrs ago

 

I still have not found any helpful information.

New today is $225

eBay sources charge $150 repair. $90 testing fee if no problems reported. $50 if found unrepairable.

ANY BETTER prices or ideas available? I am in Nebraska and find no one within this area who can do the reprogramming.....

thanks guys

 

The ground cable on the starter bolt is CRUCIAL in that generation LH body. As well as any of the 90s. There are 2 square connectors up by the wiper cowl that get a little corrosion/oxidation in them that cause a ton of PCM circuit issues.


Yes, those PCMs were garbage. But it was the 90s and people traded in 3 year old cars for a new one for things like blown head gaskets or a trans rebuild back then.

 

I took the connectors off the starter and brushed the carbon corrosion clean and put it back together. (The carbon makes it so you will likely snap the bolts and have to drill them out and replace so be prepared for a 4 hour ordeal.)

I also hooked up my truck with jumper cables to give the battery extra amps to make sure the cranking power on the van's battery is not the issue.

PROBLEM STILL REMAINS.

I am now tracing the wiring back to the fuel pump and thinking of dropping the tank to check the connections on the pump. I replaced the pump 30,000 miles back so it should still be good.

Any other ideas?

Now it is 30 degrees out and I can not get the pump relay and circuits to activate the pump even with blowing a hair dryer on the relays. AND I really need to get it going to park it in storage. Next spring I think I will waste the $90 to have the PCM sent in for testing so I can eliminate it from the scenario.

I am about to pull my tow package off and sell the van for parts. I got $425 in new rubber, new upper gaskets and tuned valves, newer fuel pump, new plugs/wires/distributor, new timing sensor, new filters, new radiator, new water pump and new brake pads and I'll be lucky if I can get $750 for it if I don't solve this starting problem. uggghh

 

have you swapped out the ECU?

 

I am again dealing with issues with my 89 ECM

The 14 way connector has been compromised by techs in the past probing the insulation next to the connector, which eventually broke the wires due to corrosion and flexing.

I thought I'd sorted it out, and my sorting did last 9 years, but it was an improper fix that came back every so often requiring cleaning and reseating connector.

The molex connectors are only rated for something like 25 insertion cycles and I've exceeded that no doubt.

Some of my socket connectors had a bare wire inserted through, which caused too much pressure be required to reseat connector and compromised the connection on potted circuit board.

I believe the Pins soldered onto the circuit board are now compromised as I can push on the base of the connector and stall the engine, or push on the other side and wiggle to get everything working properly again.

It could still be the connector, or a wire in the connector, but I am pretty sure it is now the pins connection on the circuit board. as I have retightened the sockets and dremeled them shiny so that the bad connection lies outside the mating pin/socket zone.

I've got another ecm on the way, but I have to fix this connector.

Trying to figure out the best path for completing this as it is not as if I can just order another connector with pigtails ready to be spliced in.

I guess it is off to the junk yard and find 88 or 89 chryslers which used this connector, but My ride to them is likely to stall a few times en route despite a barrage of sponges and zip ties and other methods to immobilize the connector and the wires leading to it so that it runs properly.

Moisture causes additional issues over normal heat cycling.

I hope to rebuild a junkyard connector with new barrel connectors and wires and then splice this into the current harness, rather than attempt to rebuild and resplice the current connector in the limited space underhood.

Perhaps I'll get lucky and find a junkyard connector in good enough condition that I can just splice it in without a rebuild. But murphy was an optimist.

Not fun driving when a stall is expected anytime. At least I've been able to drive away again with enough manipulation of stress on the connector and it has not occurred somewhere where I could not pull off safely.

 

Those connectors suck. Good luck with all of that. Hopefully, a junkyard connector will just be "splice, plug and play".

 

I found two 14 way ECM connectors today in Dodge Caravans and took both. None of the wires appears to have been probed in the past and insulation is in good condition.

It appears a wire or two might be thinner than what is on mine. It does not look user friendly to get a new fatter wire properly attached to the socket inside the plug as the tail end of the plug is actually formed over the wire insulation.

While in the junkyard I snagged another pop out door window( for the closing hardware), an intermittent wiper timer delay relay, some regular bosch style relays, and a pretty good condition Captains chair that cleaned up well and will need a bit of modification to fit my swivel base.

I stalled numerous times this morning and at one point, cut off all previously installed connector immobilization zip ties and pressure sponges and got a bit more elaborate, then drove off to the junk yard and back with no further issue.

I am trying to decide on someplace to have my current ECM rebuilt to have as a back up. I can solder but not so much on potted circuit boards, and the ECM has been giving a code 53(internal ECM fault detected) since day 366.

 

I tuned up the junkyard connectors with a good cleaning, and after choosing the better condition connector, extended the end of the connector with many coats of liquid electrical tape for some strain relief and extra sealing of the plastic/ wire mating area where the wire's insulation likes to break and allow the rot to begin.

After splicing new 14 way connector into the harness one by one, I plugged it in , started her up, and my recurrent code 53 did not reappear on the key dance I performed after shutdown.

A remanufactured Cardone ECM arrived today, after I realized it was the old connector responsible for my code 53 issue, and that the newer connector resolved all stalling issues.

New ECM started the van but a half second later the check engine light came on with a code 27, Fuel injector. It seemed to run OK otherwise, but CEL=No pass smog test, and no confidence.

It's going back.

I used some contact enhancer (stabilant 22) on the pins and sockets, and after seating the connector fully, injected Dielectric grease around perimeter to seal out air and moisture. In some connections, the dielectric grease can cause issues if between the conductive mating surfaces, and I think this connector is prone to them.

When cleaning the junkyard connector, there was some clear flaky substance on the interior of the sockets which flaked off when I rebent the 2 prongs inside to exert more pressure on the ECM's pins. They were mostly invisible, and perhaps it was hardened dielectric grease that would have impeded conductivity if left in place. I could not even see the pressure arms until I thoroughly cleaned with a canned electronics cleaning pressure spray and a sewing needle

I wonder how many ECM/PCM issues are really connector issues that perhaps a good cleaning would resolve. Perhaps if they are internal issues to the module, they were caused or partially caused by a bad connection here to begin with.

It woulda been difficult to see and to clean as thoroughly if the connector was still underhood. I did so on a well lit workbench and made use of a magnifying glass.