jerky car in traffic type driving...

[s1ngletracker]

I know ive had a similar issue with my civic that I was able to mostly correct via tuning... but i'm having it with my talon, and its worse, and my talon is stock.

Symptoms: when i'm driving in traffic (1st or 2nd gear, on and off the throttle) the car is REALLY jerky when i go light throttle to no throttle, and vice versa. Like ridiculously jerky, so most of the time i just end up clutching, which is a pain in the ass.

Car: 92 talon TSi awd
mods: charge piping and FMIC, 3 inch turboback, walbro fuel pump, HKS air can.

Anyone know what could be causing this? This wouldnt be an ISC problem would it? I know my ISC is shit. New spark plugs, throttle body is clean, gets decent gas mileage (21-25 mpg). New Bosch O2 sensor. I dont know whats going on.

the car MIGHT have some vacuum leaks, i have a pretty good suspicion. Could that be causing this?

Can anyone help? Thanks.