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Want to stall when I press the pedal

Posted: Sat Feb 11, 2006 10:43 am
by turbo3.4
Ok I can't figure out what to adjust to try to fix my problem of the car wanting to stall when I press the gas. Anyone have any ideas?

Posted: Sat Feb 11, 2006 11:13 am
by Bernard Fife
my problem of the car wanting to stall when I press the gas
turbo3.4.

This is typically caused by accel enrichment need some adjustment. Often it's too lean, however it may also be too rich. Generally, the highest of the accel enrichments should not be much more than your req_fuel, and may be quite a bit less.

If you post more info (msq, datalog, etc.) we can offer spcifics.

Lance.

Posted: Sat Feb 11, 2006 2:29 pm
by turbo3.4
Ok here is a datalog. the 2000ish RPM is where my idle is at for some reason. and i also included my msq. When I press the pedal i'm going lean and its has a noticable missfire. Let me know what I should fix.

My engine is a 3.4L (206CIB) with a T70 turbo and I'm running 65LB injectors.

Posted: Sat Feb 11, 2006 2:43 pm
by turbo3.4
I just did some further testing and found out that it only wants to die/go lean when i quickly press the throttle. everything is fine when i slowly press the pedal.

I'm using MSII, 2.3 code, 2.25 MT, and the V3 board.

Posted: Sat Feb 11, 2006 3:06 pm
by Bernard Fife
turbo3.4,

Right now you have the accel enrichment at:
<pre>%/s - msec
---- ------
154 15.0
80 10.0
40 5.0
10 2.0<pre>
However, given your req_fuel of 5.5, I would change this to:
<pre>%/s - msec
---- ------
220 12.0
140 8.0
80 5.0
40 2.0<pre>
That ought to run better. However, if you are turbocharged (just guessing from your handle) you might want to experiment with MAPdot as well, perhaps with 50% MAPdot / 50% TPSdot, and in the MAPdot use:
<pre>kpa/s - msec
------ ------
220 8.0
140 6.0
80 2.5
40 1.5<pre>
as a starting point. The reason you might find this helpful is that the manifold pressure on a turbocharged engine is not directly related to the throttle position.

Lance.

Posted: Sat Feb 11, 2006 4:51 pm
by turbo3.4
Ok I adjusted what you said. I have a slight hesitation still but much better than before. What should I adjust to smooth it out? Also when I rev it from idle (1100 RPM) and from 2000 rpm i'm still going way lean. when i reved it from idle it stalled on me when i let off the throttle. what should i be messing with to work out these bugs?