Originally Posted by A Bonnie Canuck
When the surge is occuring, is the torque convertor locked up? This should be readily available info on the scan tool. If the torque convertor is still locked up and it is surging, is it the engine RPM going up and down or the vehicle speed? We need to narrow the problem down to engine or transmission. Any codes?
Yes, the surging only happens when the torque converter is locked up. The torque converter slip rpm shows that the torque converter only slips around 9 rpm and when the surging occurs the slip rpm varies from -9 to 25 rpm. The engine rpm shudders a little bit while it happens and there is no dramatic change in vehicle speed.
The surging goes away if i accelerate slightly. The torque conveter slip then goes to about 30 rpm (torque converter is still locked up).Then shortly after i go to light throttle/cruise the surging comes back.
When i was using the scan tool on the way down the shore it had a historic code. It said run pndl(i forget the 4 letters exactly) switch failure. But when i went out to go look at the code agian it wasn't there according to the scan tool.
I hope i'm being clear enough. If there is any more info you need just let me know.