ECM for 93 YJ

You didn't mention new or used. Here are a few places to try.

Yes - thank you Bill - PCM new/used no difference as long as it is functional.

thanks paul

Just FYI, if the ground strap that runs from the rear of the engine head up to the firewall goes punky, it will cause a computer failure.

So can the recall on the emergency brake if they forget to hook up one wire onto the bolt there.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: Non members can still view! Jan/06 (More Off Road album links at bottom of the view page)

Some folks have been told their ECM is dead after getting the emergency brake recall done. There is a wire there on a bolt that is the ground for the fuel pump and if the 'tech' doesn't know about it, it can be left off and nothing they can do will make the pump work so they think the main ECM is dead.

The other grounds for the ECM are near the oil dipstick bolted onto the block.

It is a bit unusual to hear of a dead computer in a YJ...

Mike

paul wrote:

Well - this is all related to an "assumed" tranny problem, after having much work ($$$) done the problem wasn't fixed - Went back to tranny shop and they claimed a spark or vacuum problem. I changed plugs, wires, cap, rotor, and even the ignition coil. no improvement. Went to a recommended service shop - they told me that the crack in the exhaust manifold was causing the O2 sensor to mis-read and this created the tranny shifting problem --- well - after replacing the manifold there is no improvement in performance: From dead stop - full throttle the vehicle is slow (I6 4.0 3.07 gears - it should be like a rocket) remaining at full throttle it will wind up and not change gears unless foot is let off throttle. Then at highway speeds when trying to pass it used to rev up to 3500 rpm's with no drive train response - now (after second visit to tranny shop) it will not go over 60 mph on the freeway and rpm's remain constant (although if I put it in neutral it will rev up).

So the service shop is guesstimating that the computer is bad - but finding one is proving difficult - the service shop is continuing diagnosis to see if they can verify the computer is faulty......

thanks paul

You are describing a failure in the TPS to me.

The plug and socket on it get dirty and need cleaning on a regular basis. This controls throttle response and shifting. I recommend an electronic spray contact cleaner, but even WD40 will do in a pinch.

If you have a multimeter I can give you the electrical test info for the TPS also.

Mike

paul wrote:

I went through all connections and cleaned them and added die-electric grease.....

BUT - I got a call from the shop this afternoon and they found the problem - I got Helen (that's what I call her) back today and everything is fine - I spent WAY too much money trying to chase this problem down.

It was the distributor !

So - did I need to rebuild the transmission? I'm guessing no - and I will have a few words with them about it on Monday.

Did I need the new exhaust manifold? It was cracked but it wasn't effecting performance - but it is a nice to have as I plan on keeping this jeep for a long time.

Did I need to buy new plugs, wires, rotor, cap and ignition coil? The distributor cap was VERY corroded with that white powdery dusty stuff (maybe that was a clue) but other than that everything else was still in good condition.

All I really know is that in the last 4 weeks 'Helen' has only been home for about 5 days and I missed her dearly - it feels good to have her back (my pocket book will recover). I also am thankful that the service shop was relentless in tracking this solution down, I was really starting to worry.

Thanks to all for the tips and tricks. paul