GTP Idle Issues

[Lumpo]

My GTP has been having trouble idling only on start ups. Once it starts and smooths itself out it idles and drives great its just on them starts. When it sits all night i have to give it gas to get it to start and it will sometimes surge a bit before smoothing out. When my car is warm it will sometimes start without giving gas but will surge pretty bad. I actually have to rev it up a bit so it can smooth out enough so i can change gears without it dying. When i switched to E85 recently it got worse. Any ideas i been fighting this for sometime now i just want it fixed and i believe its in the tune. Do i need the AFR adders? I have my wideband hooked up and i have a steady 14.7 AFR at idle. I was doing some reading and am seeing people drill an 1/8" hole in the TB to allow more air at idle?

Here it is...

[awillis98]

have you checked for any vacume leaks?

[Lumpo]

Yes no exhaust or vacuum leaks.

[Lumpo]

Looking at my scan when i have key in on postion im commanding 11.5 AFR is this my problem? Then when i start my car it hunts for a bit then finally the AFR is back where its suppose to be. What you guys think?

Scan...

[passingpower]

Have you cleaned your MAF sensor? Try cleaning the IAC motor and it's bore/seat.

[xpzd3800]

I have drilled a hole in the TB to make it surge less,
what % is your IAC motor at? keep an eye on that

[Lumpo]

My MAF is clean as a whistle havent checked on the IAC i guess ill be doing that tomorrow. My whole issue started after i installed the intercooler and the 42.5# injectors. Since then my car just didnt start like it should. Then i switched to 65# and E85 and its got worse.


Here is a scan when the car is idling good after surging. When its surging i see up to 160's down to 40's IAC. Ill get a scan of it surging.

[bwkmaro]

did you modify your injector tables... theres a update that allows for voltage and feq. changes

[Lumpo]

All i did as far as Injector Tables is skewed them for my 65# and E85 you can see how i have it set in my first post.

[passingpower]

That's the thing about skewing this and tweaking that. I'ts possible to be damn fast in the quarter mile. However, you can expect street-ability issues that way. For a better explanation, read anything Greg Banish has written. Also do a search for eficalibrator and read read read. Looks like you're doing all your air fuel ratio tunning using mostly fuel. Good road manners will take a bit more work. Another good place to start looking: Bernoulli's flow equation. Find out why scaling won't cut it for large changes in fuel delivery. Take it or leave it. It's just advice for someone asking a question. I can tell you this; I tweaked around for two years before I got frustrated enough to make myself learn what I just typed.

[Overkill]

Your MAF table is an absolute mess but more than likely the issue is in your timing table at idle. Watch where it surges and smooth out the transitions in that area, or if you have access to tiny tuner, enable the idle spark table at a lower temperature so it never uses the main table at idle.

[MMGT1]

Attachment 29097

Give these a try and see how it goes man

[Lumpo]

FIXED! After logging my IAC counts and seeing that they were over 100 i just adjusted my throttle body plate to be partially opened to allow more air flow and bring my IAC counts down. Starts like the day i bought it I couldnt be more satisfied! Thanks for all the help!

[MMGT1]

maybe you should consider a 1/8" hole drilled into the throttle plate and return the plate to a closed position

[Lumpo]

Why is this?

[passingpower]

Good job! Have you upped the idle for the cam?

[Lumpo]

Cam idle is at 750.

[passingpower]

Does that still have some lope to it at 750?

[Lumpo]

Oh yeah. Personally i think it sounds better than my previous idle at 685 rpm.