Do you have to program a ecm when you install new one??

[soccerdad]

I'm trying to get my 1995 929 to act normaly again. It started flashing the check engine light and the hold light flashes off and on. It also occasionaly won't idle right and dies after it warms up. runs fine warming up then craps out and won't idle right...so i took it in for a code scan..the shop said they pulled 28 different codes off the scan and they suspected the computer was toast. cause the car still ran normaly except for the idle issues.. going back tomorrow cause they said they had a used one to put in and try out and see what it scanned to see if the old one is bad .. my question is will we need to get the new ecm programmed for it to work? there is a security system and i've heard some ecm's have to be programmed for them to work right once installed in the car...anyone got an idea about this...thanks

 

[CorkSport]

I think the 95 models uses a weird mix of ECUs. It isnt really OBDII but it acts like it.

The easiest thing would be to disconnect the battery and turn the key to the on position to open the circuits. Turn the key back off and reconnect the battery.

That should re-set the ECU.

Derrick

 

[soccerdad]

Thanks for the info I just got another ecu off of ebay for $20 and will install it and see what happens. rebuilt ones are $250 so just wanted to see if that was the problem. the guy selling on ebay said the ecu came off a running car and was good. the car has no plug for a obd system the shop used an adaptor that went on the diagnostic box in the engine compartment. covered the whole square box that has the ground and 10 pin in it and has pins that go into alot of the slots in the box. i couldnt get codes to flash jumping the ground and ten pins like you can with earlier obd systems..weird must have been between obd1 & ll hoping this cures the problem...find out tomorrow when i drop it in and see if it cures the problem...