No Overdrive after driving for a while.

[guitarsandcars88]

Aight. I'll be going down the road for a little bit. 60-70mph in OD. Then, out of no where the car down shifts to third and stays in third until it cools off. Seems to me like a valve is sticking, what do you think.

94 Olds Eighty-Eight LSS

[maxwedge]

Should scanned for trans solenoid functions and codes for starters, a regualr scanner cannot do this.

[guitarsandcars88]

I've gotten two codes for the last 2 months. Something about a quad driver failure. Its quads 1 and 4, could that have something to do with it? I've had my mechanic look at it but he doesn't know what those codes are and has had a hell of a time looking them up. I'm taking it to a transmission shop on friday. Just wanted to see what you guys thought. Thanks.

[razr_88]

here the answer your looking for on this site

http://autorepair.about.com/library/faqs/bl518f.htm

it says that "the Quad driver is like a circuit breaker inside the PCM that can control up to four different outputs on each one. Chances are there is a shorted solenoid somewhere."

it sounds like it could be just a short... whatever you do make sure they don't rip open your transmission before they check the wires going to it(happend to a friend of mine)!!

[guitarsandcars88]

Right on, they aren't doing anything that myself or my mechanic doesn't approve of.

[guitarsandcars88]

**UPDATE**

Took the car to the transmission shop today. They determinded that the QDM codes are probably causing the overdrive solenoid to not work. Since the QDM is part of the ECM, they are repacing the ECM. Also the vacuum dealy for the trans is the original and with 200,000 miles, its time to be replaced. Hopefully this takes care of the problem.

[maxwedge]

The solenoid itself in the trans can fail and affect the QDM, question the shop about this.