Ok, so I just changed my timing belt performing the 120k maintenance since I had no records when I bought the car. I pulled the plenum,did the coolant bypass fixed the leaking valve covers and installed headers. Timing set at 15 degrees, tps at 4.4V. Car runs and idles fine. I checked the operation of the tps with a voltmeter and it seems to be operating fine, but when I drive , it’s like the throttle is an on off switch. I’m unable to modulate the throttle and drive smoothly. There’s a lot of pops and crackers from the exhaust that weren’t there before, but I’m not sure if that’s because the exhaust is breathing freer or related to another issue.

A friend suggested I may be off one tooth on the timing belt. Could it be a vacuum leak? Has anyone else experienced this problem and if so, what was the fix? Thanks for any and all help.