TupperWare
Probationary Member
- 23
- 2
- May 6, 2020
-
Portland,
Oregon
I have a 98 TSi has a 6 bolt 2.3 stroker, stock 2g head, big turbo, FIC 850s, fuel pump, fpr, FMIC on speed density 95 ecu with '91 cas.
I've tested for boost leaks and verified base timing, I've been fighting with this for awhile. When I try to free rev the car when I try to open the throttle to about 12-20% especially. If I hold it there it will jump up a couple hundred rpm then stumble and almost seem to just turn off until like 400rpm. Then it will stumble to life then rev up, I've tried messing with tip in adjust.
When I give a bunch of throttle 60+% it revs up just fine with a slight hesitation. Then moving to driving, when I get off throttle and get back on even at light throttle especially that 12-20% range. It bucks like crazy until it gets past it or if I give more throttle. It does this at any rpm.
I noticed in a log, I have a wideband and simulating narrow band. In closed loop it's trying to take out fuel when I'm getting on the throttle. And coming to a stop it will be fine until I get to the last 5mph it will stumble out and die. Again it's trying to take out all the fuel when it's catching the idle until it dies.
When I lock it in open loop and the car drives almost perfect. Very VERY light stumble getting on throttle but totally bearable. But I don't want to lock the car into open loop 24/7, I haven't messed with timing tables besides taking timing out in the upper RPMs in boost to keep it safe for now.
Like I said i verified base timing, boost leaks, and installed a new TPS and is the same issue. I've never had this issue with other ECM cars I've had, and the injectors came off my old car that I also has no issue with. I'm stumped at this point. (Yes I tried looking and for some reason I couldn't find anything) I'll post a log when I get my laptop back, I'll post an idle/rev and a cruising log.
I've tested for boost leaks and verified base timing, I've been fighting with this for awhile. When I try to free rev the car when I try to open the throttle to about 12-20% especially. If I hold it there it will jump up a couple hundred rpm then stumble and almost seem to just turn off until like 400rpm. Then it will stumble to life then rev up, I've tried messing with tip in adjust.
When I give a bunch of throttle 60+% it revs up just fine with a slight hesitation. Then moving to driving, when I get off throttle and get back on even at light throttle especially that 12-20% range. It bucks like crazy until it gets past it or if I give more throttle. It does this at any rpm.
I noticed in a log, I have a wideband and simulating narrow band. In closed loop it's trying to take out fuel when I'm getting on the throttle. And coming to a stop it will be fine until I get to the last 5mph it will stumble out and die. Again it's trying to take out all the fuel when it's catching the idle until it dies.
When I lock it in open loop and the car drives almost perfect. Very VERY light stumble getting on throttle but totally bearable. But I don't want to lock the car into open loop 24/7, I haven't messed with timing tables besides taking timing out in the upper RPMs in boost to keep it safe for now.
Like I said i verified base timing, boost leaks, and installed a new TPS and is the same issue. I've never had this issue with other ECM cars I've had, and the injectors came off my old car that I also has no issue with. I'm stumped at this point. (Yes I tried looking and for some reason I couldn't find anything) I'll post a log when I get my laptop back, I'll post an idle/rev and a cruising log.
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