1999 Oldsmobile Alero PCM Replacement

For Olds Aurora and Cutlass to the Alero and Delta 88.
Ask our auto mechanics for help to all your Oldsmobile car questions.
Post Reply
sleak300z
Posts: 2
Joined: Tue Jan 01, 2013 6:28 pm

1999 Oldsmobile Alero PCM Replacement

Unread post by sleak300z » Tue Jan 01, 2013 6:29 pm

shawnee (1/1/2013 2:14:29 PM)
i have a 1999 3.4 olds alero, which i have dropped a 2001 impala 3.4 in. i recently replaced the heads on, got all back together and started it. it had a random cylinder misfire, after new wires and plugs, coil packs(all of them), i came to the conclusion it was the injectors. so i remove them cleaned them and reinstalled them, started it and got only a #6 misfire. so i pulled the plug, it was soaked w/ gas, so i switched #5 and #6 injectors, to see if it was just a bad injector, and got random cylinder misfire again. i pulled both plugs and 6 was wet but 5 was dry. after checking for any open grounds or breaks in wiring,i figured it was the PCM. i bought one from a 98 3.1 malibu, same exact SVR number and the pinout is exactly the same, but after plugging this one in and turning on key it doesn't turn on the fuel pump. do you think this one is bad too, or do i have to have it flashed?

 

User avatar
ProTech
Posts: 665
Joined: Wed Oct 17, 2012 10:08 am

Re: 1999 Oldsmobile Alero PCM Replacement

Unread post by ProTech » Tue Jan 01, 2013 9:47 pm

Your first mistake is buying a used PCM, especially from a different model and year. The reason it won't start, or basically do anything is because it is currently programmed to the other vehicle. You CANNOT re-program the used PCM to your current vehicle. If you feel you do have a bad PCM, you would have to buy a new one and have it programmed at a dealership.
GM Dealer Technician For 18+ Years
In the automotive industry for 20+

sleak300z
Posts: 2
Joined: Tue Jan 01, 2013 6:28 pm

Re: 1999 Oldsmobile Alero PCM Replacement

Unread post by sleak300z » Wed Jan 02, 2013 12:12 am

that is not what was wrong and the programing is exactly the same from the interior wiring to the engine. same car different names, like firebird and camaro. but i thank you for your input, even if it was wrong. i had the plug wires mixed up on 2,4, &6 but she starts, runs, and doesnt get hot or misfire.

User avatar
ProTech
Posts: 665
Joined: Wed Oct 17, 2012 10:08 am

Re: 1999 Oldsmobile Alero PCM Replacement

Unread post by ProTech » Wed Jan 02, 2013 10:30 am

I'm afraid you're the one that's in the wrong, pal. You've got a big misconception about 'programming'. It has nothing to do with the wiring, even if it is exactly the same as the donor car. You give the example of a Camaro and Firebird being the same, which in terms of the same body code 'F' you are correct. Try taking a PCM out of a Camaro and put in the exact same year/engine Firebird and the car WILL NOT START! When a PCM is programmed at the dealership, it goes by the vehicle identification number and options, that's why it will not work in another vehicle. So, even if the PCM you tried to use was from an exact duplicate car to your Alero, it STILL WILL NOT WORK!!! Please don't try to tell me my job, I've been doing this a lot longer than you.

If you want proof, and since its seems you messed up the plug wires and now it runs fine, try plugging in that other PCM and see if the car starts....I guarantee it WILL NOT!

Have a great day!
GM Dealer Technician For 18+ Years
In the automotive industry for 20+

Post Reply