2001 GTP E85 tuning/cold start and cold idle problems

[Mike01gtx]

Hello everyone, I'm looking for some input here. I have a 2001 GTP that has been converted to E85, the car also has a zzp NIC cam, Northstar throttle body, LQ4 MAF and 60# injectors. It seems to have some cold start/cold idle problems. When cold starting it will not start without pushing a very little on the gas pedal and won't stay running without keeping your foot on the pedal.

However if I keep my foot on the pedal and get the coolant temp to normal operating temp it will idle on its own with my foot off the gas pedal. I'm thinking this is most likely a tuning issue? Any opinions/help? I can post the tune if need be, I have a show I am planning to attend in 4 weeks and really need to get this going.

Thanks in advance!!

[Mike01gtx]

Bump, anyone? Gotta be some 3800 tuners here.

[5FDP]

Post you tune.

You are pretty limited on what you can do, there is barely any control over these 3800 computers as they are pretty stupid compared to a V8 controller.

Maybe increase the idle speed on cold starts, play with the VE and timing to see if you can keep the rev's up. There are no idle airflow tables to adjust so you may have to improvise or just deal with the tuning issues of E85 on a car like these.

[IARLLC]

Maybe you already adjusted this but...on the L67s and most 3.8s there is a minimum air rate "adjustment" on the lower/side of the throttle body (back toward the strut tower in your case). Should be a T10 torx and an 8mm set-nut (not that I have ever done this...) It is not supposed to be "tampered with." BUT in the case that the engine is no longer stock and/or has some other reason to need more air on initial start-up (E85)....you should be able to give it a half-turn or maybe more without any issues. Lots of Idle Air Control motors just don't get open far enough for good reliable cold starts. If I remember correctly the P04 ECMs were looking at throttle position every time you start the car and calling it 0%. I recall more than a few starting/running bad if the owner had the habit giving it "some gas" while cranking. My point would be that if you give the screw a bit of adjustment the ECM will still see it as 0%...worth double-checking though.

[507]

You can ask HP tuners to open up more tables if you know what tables are looking for.

Plus the NCI cam has lots of over lap. Might wanna ask zzperformance if injection timing needs to be adjusted for the Over lap of the cam.

I know there is a program that will allow you to access a lot more table. But ask HP tuners first. I know they can open the tables you might need.

[IARLLC]

That would be great! The P04 tables are lacking. Maybe IAC start-up tables from a cable tb F-body would have the same number.? The ECM has to have settings for such.

[507]

That is yes the best part of tuning. Getting it 2 work 4 the V6. Or use Power Tuner and Tiny Tuner.

I Say Work with HP Tuners.