Even after all the work I did on my car, I rebuilt my own transmission, new torque converter, testing my TCC switch, etc. I still get surging. All though not nearly as often as before I adjusted my TCC switch. I suggest turn the switch in 1 tooth and try that, then adjust again if needed. I find mine surges mainly around 45mph, in 4th gear with TC locked. Start going up a small hill and the engine load goes up, but still stays locked up and will surge. I now simply reach down and shift in the 3rd gear and all is well. Then at the top of the hill shift back to 4th. Over the years I have heard many people complain of the same problem. It can be minimized with adjusting the TCC switch, but rarely seems to go away all together. Seems to be a inherent problem with our cars. I even went in and played with the tune in the PCM a bit. My belief on this is a small tuning error where things like throttle position, load, speed, and gear all over lap and cause a conflict. The torque converter then goes in and out of lockup.
SAVING THE WORLD ONE BONNEVILLE AT A TIME
1997,1998,2000,2005 year confused Bonneville SSExi. Stock? ish.
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