Crazy bucking freeling from car while driving

[carbonfire]

Ok, so I have a 91 TSI AWD... GO Anyway... I am driving it, does not really matter what kind of boost I am running, or how fast I am going, but just driving the car. Sometimes when I hit 2nd gear and sometimes in later gears I get this bucking sensation. Like the tires skipped over the ground, or someone hit the brakes for a split second, and than everything goes back to normal. I dont know what the deal is.

Could it be my T-Case low on oil.... I looked under the car and saw it dripping a little out of what appeared to be the yoke. And it smells and tastes like gear oil. So I am either guessing that it is leaking or spraying oil out a vent hole or something.

My car was an Auto but now is a 5 speed.... I wonder if that will make any diffrence to the dealership. I am sure they can tell some how but who knows. Anyway what the heck is that bucking... anyone have it before?


Alex

 

[DSM90AWD]

And it smells and tastes like gear oil.Alex

scary how all us veteran DSMers know that taste well

What you describe may be a Center Diff issue. Do you have any "jerkyness" when making sharp turns in reverse?

BTW.. the XFer case fluid level is easy to check. You just keep adding till it runs out the top fill plug. Also.. there is a recall on the DS Yoke which the dealor will check/replace for free if the seal is bad.

 

[CurtTSI]

My guess would be that your throttle position sensor is bad. It sends a signal to the ECU to tell it how much the throttle is open. Sometimes, a dead spot on the sensor develops which causes it to buck while you are driving. I had this happen to me and the TPS tested good during resistance tests. Finally I connected a volt/ohm meter to the output from the sensor and mounted the meter on the outside of the windshield, so I could look at it while driving. I found that when ever the engine bucked, the output voltage went to zero. Replaced the TPS and the problem was solved.

 

[carbonfire]

I am almost positive that it is not the Center Diff becasue I have a 4 spyder one and I dont have any problems turning or in reverse. It is only when I am going streight and at about 3/4 throttle or full out... never under that... so I bet your are right saying it is the TPS... I will see if we have one at my work tonight and see if it fixes the problem.


Alex

 

[carbonfire]

Well I guess I am not convinced that it is the TPS.

could it be some sort of fuel cut... a friend of mine said that is most likely what it is... does it realy bad when it is really cold out and when the motor is getting gobs of cool air.. and it also does it less under full out boost. I dont know.. .could it be a bad fuel pump also or what?