new ECM on 1993 Lumina car and still stalling

Hi,
After extensive work on my car, I had the cam shaft replaced to the tune of $1200, ran good for 3 weeks, then started jerking and stalling, so I was told the ECM was bad....so replaced that for another $220 (Same mechanic). After 1 day, the car still stalls, and on occasion the speedometer jumps from 30-50mph. The mechanic says it is just the ECM memorizing the cars running habits? Has anyone else had this problem and if so, what is the cure for it?
The car has been great on trips and has loads of power. The mileage is 127,000
Thanks,
Peter

That sounds like an electrical problem. Check to see that you don't have any broken wires. I had the same problem. The speedometer jumped from about 50 all the way over to 80. I had a broken wire somewhere in those wires that went to the ECM.
Where did you get your ECM from? $220 is double what I paid for mine. I got mine from Advanced Auto Parts for $90 plus. It was $180 but the core charge was $90-something, too. I think it was $94.

That sounds like an electrical problem. Check to see that you don't have any broken wires. I had the same problem. The speedometer jumped from about 50 all the way over to 80. I had a broken wire somewhere in those wires that went to the ECM.
Where did you get your ECM from? $220 is double what I paid for mine. I got mine from Advanced Auto Parts for $90 plus. It was $180 but the core charge was $90-something, too. I think it was $94.

Thanx for the reply Jay. My problem is worse in the morning, like this morning I drove the car back to the mechanic and the car was jerking and the speedo kept jumping and the service engine light kept flashing on and off. Hopefully they can find the problem today.
The cost of the ECM (they didn't want the part from Advanced....I think it's a commission thing) was $120 for a rebuilt one and the rest of the price was labour.

If it's jerking, it might be the crankshaft position sensor. Have they done a diagnostic check on the car? If they do that, the ECM should tell them what is wrong with the car.

If it's jerking, it might be the crankshaft position sensor. Have they done a diagnostic check on the car? If they do that, the ECM should tell them what is wrong with the car.

Hi Jay,
I just got a call from the mechanic and what it was was that they found the rebuilt ECM to be faulty and replaced it. I drove the car yesterday and it seemed to behave ok. Hopefully that was the problem. Thanks alot for your replies, I sure appreciate it!
Peter