Surging, off power
Bought a real nice 97, 4.6 a few months back and while the car was in really nice shape overall, it was kind of a dog to drive. The P.O. mentioned that the car might have an issue with the TPS and after reviewing a bunch of threads here, I came to the same conclusion. In any case, I went to my local Ford dealer and picked up a new TPS and installed it. There was no noticeable difference and the car now had an error code. I took it to Autozone and they plugged it in to their diagnostic tool. Turns out the TPS was not getting the voltage it required. I took the TPS out and swapped it for a new one at Ford. The good news is that did the trick as far as the car being a "dog" to drive. It had full power, shifted nicely etc. It did present a new problem however. If I'm accelerating and I get OFF the throttle, the rpms will "surge" for a second or two and then even out. It goes from say 1100 rpms up to 1500, back down to 1100 and then back up to 1500 in rapid succession. Then, it evens out.... until the next time I get off the gas. The problem is consistent in that it happens every time I let off the accelerator. Any ideas?? Thanks!