I've has this problem for some time now and I cannot find the cause. If I am driving between 40 - 60 MPH and let off the gas, then slowly give it gas again, the car will jerk or lurch. It almost feels like the engine mounts are lose (they are not lose). Sometimes it will also jerk right when I let off the gas.

The jerking does not happen all of the time. When I first start driving it will be fine, but after about 5-10 miles it will start jerking and only lasts for a few miles then will be fine again.

I am getting no codes and have no other problems. I have replaced the plugs and wires, fuel filter, trans fluid replaced, 02 sensors (different problem), all of which did not help. Had the trans looked at and no problems were found. I also removed the coil packs, cleaned the contacts and added some dielectric grease to them.

Anyone run into this problem before or have suggestions of what I can try?

Any clunking sound involved?

No sounds at all.

Does it perhaps happen at 48mph, and your RPM'* drop slightly right afterwards?

I had this same problem that I noticed right after I purchased my car. I was told that it was torque converter shudder and a little bit was normal. I really couldn't notice mine unless I was travelling around 45mph and going up hill. Any other time, the lockup of the TC was seemless. The dealership I purchased it from could not replicate the problem so there was no problem in their mind. I really don't notice it anymore, but occasionally I'll be driving around that speed and will notice it.

Next time it happens, try tapping the brakes with your other foot and see if the shudder goes away. If it does, then it is definitely the TCC (torque converter clutch).

not necessarily, tapping the brakes will unlock the TCC, so if it is another driveline problem that may be casusing the symptoms it will also likely disappear

That is what I was told by the guru'* here when I had this problem. Just reiterating what I was told way back when.

This does not happen at any certain speed and the RPMs don't jump when it does happen.

I will try braking the next time it happens and post what happens.

Mine does the same thing....it'* very annoying and I keep it in second around town just avoid it happening...also I have to give it enough throttle to force a downshift when needing to accelerate on the freeway....else it will do the same thing. It starts bucking and jerking...

Did you happen to notice what the boost gauge was reading at the time? My friend'* 00 SSEi would do that when just entering boost. I did the boost bypass as a test. The problem has gone away. Now I'll have to check and see if it'* the boost control solenoid or the actuator causing the problem. You may want to try that for a test. Be aware of the cautions listed here if you do.


http://www.bonnevilleclub.com/forum/...ic.php?t=40712