car is jerking @ 3700 rpm

Wolli · Post by **Wolli** » Thu Nov 26, 2009 8:31 am

there are so many good tuners in here, i hope one can help me.
my fully built and turboed civic b16 is only jerking @ 3700 rpm with wot. i cannot find a failure. i thought it must be the ignition, but i have changed the distributor, spark plugs and wires to stock for testing. no change.
i can stay with open throttle, but the car is just bogging, and will not rev higher till i let the throttle down to about 30%. when i am above this point it´s running normal till rev limit.
how you can see at the log the turbo is also not boosting more, the map stays still when this happens.
from 7:54-7:56 i have captured it.

fly_n · Post by **fly_n** » Thu Nov 26, 2009 10:58 am

The last time i saw a fuel map like that,was when the calibration file had been corrupted.

That fuel map is chaos dude,particularly around that 3500rpm/8psi mark,u need to find a better tuner,check your AF's coming into boost.....

Your TPS needs calibrating as well,doesnt seem to reliably sit at 0% off the throttle.

Also, is it really cold where u are,like below freezing, or is your air temp sensor under-reading?
Or maybe your water/alch injection is permanently on or something?

Wolli · Post by **Wolli** » Thu Nov 26, 2009 11:36 am

the temp is in celsius. but it was the same in summer. i tried to go more lean and rich, no change. also tried with and w/o alcohol, also no change. made a new mapping yesterday, for the case of a software problem, also no change.
this problem started slowly in summer, and got worse. car ran great before w/o a change. that was the reason for changing the ignition.

phialude · Post by **phialude** » Sun Dec 13, 2009 2:18 pm

humm.

Wolli · Post by **Wolli** » Sun Dec 13, 2009 3:18 pm

what means humm?

Wolli · Post by **Wolli** » Mon Dec 14, 2009 7:47 am

fly_n, do you think my bdl throttle body can be the reason, or a shitty fpr? i always thought, that just the ignition is mighty enough to keep the engine off from spinning higher.