Quick Nick Posted December 1, 2007 Report Share Posted December 1, 2007 Nice looking site! (I just registered) I need some help chasing down a problem in my 92 GP B4U, 3.1, 140K on it. It will idle fine, then all of the sudden it sounds like its dropping cylinders (missing) then it snaps back out of it. The SES light comes on, it flashes code 43 I belive (knock sensor). There is no audible knocking, I even chaged the knock sensor just for kicks. It does it very randomly, I cannot "make" it do it to help chase down the problem. It happends in all gears, the only time you cant actually feel it is when your physically moving. It never dies but sounds like it wants to when in park or sitting at a stoplight in gear. I've been chasing this down all summer! I'm positve there is no internal problem with the engine causing the knock sensor to go off. The car is in good shape and mechanically its very well taken care of. I've tried and tested everything on the car, no luck. The only thing I havent messed with is the MAP sensor-not sure how to check that. There are no vac leaks, compression is fine, everything checks out OK. The last idea I have is a timing chain (?). Its the original one, and at 140K its probably tired. Possibly its stretched out and the slop in it has the cam/crank/ignition all running slightly off, just enough to make it run bad randomly? Heck, I have no more ideas, help! Thanks! Quote Link to comment Share on other sites More sharing options...
GP1138 Posted December 2, 2007 Report Share Posted December 2, 2007 I'd check the knock sensor connector, and wiring. Make sure that's all good, put a DMM on it and wiggle the wire and see if there are any fluctuations, maybe it's grounding out or touching another bare wire somewhere. After that, I'd put a screwdriver on the timing cover and use it as a stethoscope and run the motor and see if you can hear anything abnormal. I doubt the timing chain would be bad at 140k though, it's pretty rare. Quote Link to comment Share on other sites More sharing options...
Addicted To Boost Posted December 2, 2007 Report Share Posted December 2, 2007 My TGP was doing the same thing before I put it away for the winter, except no check engine light or anything. I have no idea what is wrong with it. Quote Link to comment Share on other sites More sharing options...
Quick Nick Posted December 2, 2007 Author Report Share Posted December 2, 2007 Thanks I will try the connector & wiring. I did wiggle the connector with the engine running (that was exciting!) but got no change. I didnt chase the wire up though, hmm... It should wind its way up into the ECM correct? Shouldnt be too hard to run it down. Thanks for the idea, appreciate it very much! Quote Link to comment Share on other sites More sharing options...
ns87 Posted December 2, 2007 Report Share Posted December 2, 2007 Mine does it right now. My sensor is physically broken and I've wedged the wire in for now. That is so annoying (code 43). It sucks any of the little power/acceleration out of the 3.1 Quote Link to comment Share on other sites More sharing options...
AWeb80 Posted December 2, 2007 Report Share Posted December 2, 2007 Cracked Coil? Crank Sensor Bad? Plug Wires In Good Shape....Any Arcing? What Shape Are The Plugs In? Old, New? If Old, What Do They Look Like? Quote Link to comment Share on other sites More sharing options...
z34duck Posted December 2, 2007 Report Share Posted December 2, 2007 coils would be my bet Quote Link to comment Share on other sites More sharing options...
Euro Posted December 2, 2007 Report Share Posted December 2, 2007 Definitely not the timing chain. If the timing chain went bad....you'd hear a bunch of clunks, then the car would die. And would not start. Bad timing chain=rebuild depending on how bad it blew up. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.