RPM Surge

[drenfro56]

1995 with AT - at about 1500 RPM there's a sudden surge in RPM's (about 500 RPMs) for a short burst (1-2 secs), almost like a downshift. It happens under constant speed, no load, no hills. It doesn't do it all the time. Sometimes it will do it at 2000 RPM. I recently replaced the CPS. There's no codes. Any ideas???

[tinlizzy]

I had similar prob, but also abs light, no brake lights few other things cant remember what else, ended up being multi function switch.

[1995psd]

do you have any upgrades (fill out your sig)

[drenfro56]

No upgrades to engine. Trans rebuilt at 175,000, has 275,000 now. I'm wondering if its a TC slipping?