94 LeSabre Won't Upshift Under Hard Acceleration

I have a 94 LeSabre. I drive it pretty easy and it's perfectly fine that way. Although when I accelerate hard or push the pedal down and make the car downshift. It sometimes won't shift to the next gear and it'll just stay in that gear for about 7 to 10 seconds. Then usually the "Service Engine Soon" light will come on and it will shift? Anyone have any ideas as to what's going on that triggers this light?


Thanks!

More than likely, you have a quad driver fault in the PCM. Quad drivers supply the ground for the shift solenoids. You could also have a bad solenoid, but it is much cheaper to replace the PCM first. You need to find a shop that still has a scanner capable of communicating with the 94 OBD 1.5 PCM and see what the code is. Typical OBDII scanners will not work.

How would I got about getting a PCM, I'm going to the junkyard tomorrow. Would grabbing one there be good? Say out of a 1993 LeSabre?

1993 was OBDI and would not work. IIRC, 94 & 95 are the same, but you will need to change the prom and use the one from your existing unit. You will see a cover on the side of the PCM, remove the two small screws & cover to access the prom. BTW, you can get a rebuilt PCM at O'Reilly with a lifetime warranty for less than 100-bucks. Good Luck!

Edit: I found the info on the PCM/ECM you will need;

#16183247 LeSabre '94-95 Elec Cont Module (ECM); (6-231, 3.8L)
Application: 1994-95 3.8 V6 SFI “L” L27
1995 3.8 V6 SFI “K” L36
1994-95 3.8 V6 SFI supercharged “1” L67
1994-95 truck 3.8 V6 SFI “L” L27

MEMCAL IDs: “L”: BMYU, …
“1”: …
“K”: …
EPROM type: 27C512 (http://www.cruzers.com/%7Eludis/p4pinouts.html#16067633)
16183247