Engine Performance problem
1993 Pontiac Bonneville 6 cyl Front Wheel Drive Automatic
I recently replaced the plastic upper intake manifold on my Bonneville. I had to do this because I cracked the old one putting it back together after replacing the intake manifold gaskets. When I assembled it with the cracked upper intake it ran fine, but the reason I had to replace it is because it was starting to leak coolant from around the area I cracked. I went to a local junkyard and got an upper intake and throttle body from a 93 Buick Park Avenue (it was a 3.8L and looked identical to the engine in my Pontiac). Everything bolted up just fine, but for some reason the car will not run now and blows a very dense smoke when it tries to start. It's definitely an intake issue, and I've been over the vacuum lines and sensors a hundred times, and everything is connected correctly. I don't have any OBD devices or anything, but I'm thinking it may be a problem with the mass airflow sensor. The MAF sensor on the new throttle body was stamped with different numbers, so I did try the old MAF sensor with it, but it did nothing. When the engine turns over, it sounds as if it is choking and backfiring, but when it fires, it runs up to about 2500-3000 RPM and then shuts down. It's acting as if it's carbureted and someone left the venturi on the back of the carb open. It just fires and dies immediately. If you have any answers for me, I appreciate it! I'm trying to isolate the problem so I don't end up buying a new MAF sensor when it's not really the problem. Spending 140 bucks for no reason would suck. Thanks!
have the same problem?
Monday, November 16th, 2009 AT 2:33 PM