Car hesitates/stalls under 2300rpms

[Alex in Houston]

Here's an issue I'm having that has me stumped.
From idle up to 2000rpm, car has hesitation/missing while driving and cruising.
Once you make it to WOT (have to baby it up to there as it bucks/surges like there is no spark present all of a sudden) It's not present.
As soon as I get above 2200 it goes away completely. It feels like a miss on one cylinder. (this also gives me bucking just off idle).
Up until yesterday my little rich/lean guage had been showing full rich whenever it was running, no matter what. So while stuffing the computer back into the kick panel (took a bit with the twEECer adapter on it, but I got it all in there and the panels back on) I decided to re-organize the grounds. I took all the grounds at the computer (pins 20, 40, 60) and soldered on a 10 guage wire to each of them and then ran the wires back to one and ran that wire to a ground that I have coming from my battery (it's in the trunk) under the rear seat. Low and behold the rich/lean guage now shows the 02's switching (albeit slow) and not just pegged on rich. Funny thing though, the car still has the hesitation right off idle, up to about 2300 rpm's. I also get a hesitation (like it's not sparking) in between shifts.
I've looked all over the WWW trying to find some info on what could be causing this, no luck so far.
Really would like to get it on a dyno with a wideband and see what it's actually doing. Once I get back to work (unemployed at the present time, so no money to throw at the car) getting a good dyno with WB tune is a high priority.
But until that point and time, any ideas on what to check out?

[Saleen91]

do you have a maf xfer function plugged into based upon the maf that's actually in your car?

If so, try leaning out the lower part of the curve by 10% and see if that fixes it.

Paul Booth wrote a tool called the EEC Editor (link is on www.tweecer.com) that works wonders for "editing" the MAF curve like this. Those feature will be included in v 1.20 of Caledit.

Also, what size injectors do you have and what's your hi/low injector slopes set to?

[Alex in Houston]

Originally posted by Saleen91
do you have a maf xfer function plugged into based upon the maf that's actually in your car?

Yep Yep, Pro-M 30


, try leaning out the lower part of the curve by 10% and see if that fixes it.
Actually have one program (switch 3) that has it leaning out points 1-10 3%. I have switch 4 set to add 10% betwen points 18-24. I think it's switch 3 that causes the check engine lite, I'll ahve to double check that. But if so, leaning (by MAF transfer) made it a bit worse.


wrote a tool called the EEC Editor (link is on www.tweecer.com) that works wonders for "editing" the MAF curve like this. Those feature will be included in v 1.20 of Caledit.
I pretty sure I have the file on one of my rigs here, I'll look into actually using it :)


also what size injectors do you have and what's your hi/low injector slopes set to?
30# with the high slope set for 30 low slope set for 36

[HangNail]

i doubt its something so simple, but i had a similar problem with the surging on my car. turned out to be a broken plug wire.