Mechanics

ENGINE COMPUTER

1991 Dodge Dynasty

Computer problem
1991 Dodge Dynasty 6 cyl Front Wheel Drive Automatic 100511 miles

I have a 1991 dodge dynasty 3.3l v6, automatic trans, cruise control and no antitheft. Last July, 2007.I went out to go to work, and, the car just started and died, over and over, would start and shut right down. Towed to mechanic, who proceeded to troubleshoot: tac valve asmy, cam-map-crank-sensors decided it must be the ecu. To save me money got a used ecu, 1991 new yorker, no.4686430, (I looked on casing later).I'm sure he used number off original. Anyway, It lasted four months.I stopped at a store, came out and the same problem. Starts up and dies right down over and over. Of course I called the same mechanic, who did some diagnostics and said its probably the used computer. So, we purchased a remanufactured ecu, at a higher price, and then it didn't start or would start sometimes and not others. He has replaced many parts that you would think pertain, asd, speed, etc. They thought it could be a bad injector, then, the harness itself. This has been over a month now, from about Dec.10,2007 to today, Jan 21,2008.
Any help would be Highly Appreciated, and I read where the revised sbec-4686442 could help!Can I use this in place of the 4686430 ecu? I'm in dire straights! Please help! Dave
Avatar
Davdwm
January 21, 2008.




As far as cross-referencing the ECM's, gonna need to ask the dealer or have it looked up in the parts book to see if it crosses over. Has he checked the ASD (auto shutdown relay)? Have replaced many of them for this kind of intermittent problem

Tiny
Jack42
Jan 22, 2008.
Thanks for your reply and yes he has replaced the asd relay, and today I asked if it cuold be the ignition switch. He said he thought of that and they checked it out and even bypassed it. It will start, they just don't know when.

Tiny
Davdwm
Jan 22, 2008.
Maybe the ECU upgrade is what it needs. Did you ask the dealer about the interchangeability of the two comps? When it doesnt start what is missing? Spark, fuel press or injector pulse?
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Tiny
Jack42
Jan 23, 2008.

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