Originally Posted by Muslimsteel

On my sisters 1992 Buick Regal Custom (has a Series 1 3800 but different tranny than my 94 though right?) she first noticed this like jerking and thought it was going to die or something but anyways i took it out to figure out what could be causing it...after a few drives i've found that when the car gets around 50-55mph and goes into overdrive it starts kinda jerking back, feels like a huge quick gust of wind hits the front, the jerking is really spontaneous...ive checked all the fluids and air filter those are all good...when it was doing that once i switched it to regular drive and it stopped. Also my dad talked to a mechanic about it and he said it might be the overdrive lock? (not sure what that is) and that you can cut a certain wire and it will stop. im not sure if that is the best solution so i thought id see what you guys think. i definitely know its something to do with the OverDrive just not sure what. the engine has 106k on it btw if that is any help. Thanks!

Originally Posted by kimosan

This message was a long time ago, but i just went through this so I though I'd add some info. I just acquired a 1991 Riviera (75,000 miles). When climbing a grade in overdrive the car bucked a bit when dropping in and out of overdrive (OD). I read lots of posts about OD selonoid issues but I suspected a dirty fuel filter. I changed the filter and the situation improved but didn't completely stop. I could smell gasoline when getting out of the car after a drive so I suspected a misfire. I checked the ignition system and found that the middle spark plug wire (in the back-hard to see) was not connected (but close enough that it might have been firing some). I plugged it in and it was fixed. And has more power. What a sweet ride.