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Debian Dog
July 9th, 2010, 02:31 AM
Hello all finally got the beast back on the road and time to deal with issues I have been avoiding. The 2 main things that are bothering me are the idle during startup. i.e. the car starts it will run to 1500-1700 RPMs for a few seconds (up to say 10) then, usually, settle down to the set idle RPM of 850 or so. The second thing it does that is more troble some is that when it is "crusing" at say 55 MPH and little or no throttle is needed it will act like the cruise control is set. Again running at 1500-1700 RPMs. Mods that may be effecting this include K&N air filter, lid, Granatelli MAF, Yank 3800 stall, and drilled throttle body (I drilled it before I had a Flash tool, I know it is not "good".

Anyway do you think it is possible that I can "tune" it correctly without getting a new TB? And if I can tune it where should I start?

Debian Dog
July 14th, 2010, 03:00 AM
OK well this thread http://forum.efilive.com/showthread.php?4661-Idle-Tuning-Helpful-Info-Inside got me more than 1/2 way there. The car is not jumping around gear to gear and if anything the idle is a bit too low now. But I think I can fix that.

Now for the "rolling idle" issue. Any ideas for that?

swingtan
July 14th, 2010, 09:42 AM
As per usual, post the tune and a log file of all conditions.....

There is a good chance that the drilled TB blade is letting too much air through so the car will try and drive its self. The other thing to look at is the MAF as it may not be calibrated correctly in the tune.

Just as a reference, I'd guess that a cam like you have would want around 8.5gm/Sec to 9gm/Sec of idle air when warm. If the hole in the TB is too big and the MAF is not reading right, it could be over feeding air into the motor. That coupled with some possible idle reverberation could be messing things up a bit.

Simon.