Another tip-in jerking question........

thething96 · Post by **thething96** » Mon Jan 11, 2010 5:04 am

It's not letting me download the log, It's late as sh1t(actually, early as sh1t!), I'll keep trying later....

thething96 · Post by **thething96** » Tue Jan 12, 2010 12:16 am

Here's a better cal and log. The previous log I was trying to upload was not good, so I made another one.On this latest log, I made the testing on 5th gear, as close to 2000 rpm as possible, and also tried some 2500-2700rpm testing.As said before, the problem is not as bad, but still there. If you look at log, some times afr's go real lean for about 50 miliseconds, and sometimes they don't lean, but it's bucking non the less. And at the same lean afr spot, with the same mbar and throttle, the afr's go back to normal right away. Doesn't make sense. I thought that what everyone was suggesting might really be it, but the lean spike and jerking are not all related to the tune. Take a look and see what you guys think. Thanks...

ninezeroteg · Post by **ninezeroteg** » Tue Jan 12, 2010 8:06 am

Made a few fueling changes, tell me if it changes anything.

thething96 · Post by **thething96** » Tue Jan 12, 2010 11:56 pm

ninezeroteg, I tried your cal today. Car runs good, but it feels the same as with my cal. I even made a log with your cal. The test spots were using 4th mainly, same rpm as before. It's hard to pinpoint why it leans out sometimes. Example, if I'm on 6% throttle and go to 7, then 8(same increase values to mbar, from 410-470), in between 7 and 8%, the bucking happens. Sometimes it leans, sometimes not. But right after it leans out, almost instantely it'll go back to normal afr's, even in a 1% difference, which is making me crazy(this happens close to 456-465mbar, as far as I can tell)!!! Also, idle is NEVER CONSISTENT. And cold idle is not stable. Even if I have moving idle at 1000rpm when warming up, the car still wants to be at 1400rpm, this is at about 80-140 degrees. And even warm moving idle is NEVER consistent as well. Sometimes moving idle is 800rpm, at other times is 1100-1200rpm. That's what made me think it had some sort of vacuum leak, but logs prove otherwise. If it's an electrical issue, then I'm SOL, because I don't know much. Take a look, Thanks...

thething96 · Post by **thething96** » Thu Jan 14, 2010 12:27 pm

Tried some things today. Ran the car without tps, then without iacv, and nothing. Changed the hose and check valve going to the brake booster in case of a minor leak, and nothing. Tried a different set of wires, and still nothing.........

thething96 · Post by **thething96** » Fri Jan 15, 2010 3:03 am

Any one???

marshall.hagen · Post by **marshall.hagen** » Fri Jan 15, 2010 1:04 pm

I still think it is drivetrain related. I think you should inspect your clutch disc and flywheel surface.

thething96 · Post by **thething96** » Fri Jan 15, 2010 10:02 pm

marshall.hagen, I know you mentioned that you had a similar problem with a car you were working on, but on the car that you fixed, were you leaning out when the bucking was happening or was it just like a studder of some sort? And what rpms and throttle was this car doing it? Because my car does it between 1500-4500rpm(haven't tried any higher up in the rpm's), and most of the times it does lean out, which is real weird.