Engine surge on start

[Sachse]

I've got a 93 Gt with a built 302. Here are some of the performance parts:
Tremec 3550 5 speed tranny
Trick Flow stage II Ports twisted wedge heads flow .311 intake side 2.02/1.60
Gt 40 Intake fully ported to heads Felpro 1262 gasket
Eagle H-beam rods
JE Pistons cut for the Trick flow heads
B-cam
1.6 Comp cams Pro magnum Roller rockers
75mm Bullet Pro-M mass air for 30lb
30lb motorsport injectors
70mm Edelbrock/BBK throttlebody
mac short tube headers
Mac off road h-pipe
2 chamber flows


Heres the problem. When I start the car up it will surge from 1000 to 1500 and it gradually stops surging into a normal idle.

A friend said it could be the computer adjusting to all of the performance parts and I may need a custom chip burned.

Has anyone had this problem or possibly know what it could be? I had the MAF re-calibrated and had the TB checked. Any help appreciated.

[Mendari]

I agree with your friend, your 5.0 is flowing at a much higher CFM than it did with the factory programming. It's either the factory programming or the Idle Air Control Valve is overly-eager. Have you reset the computer?

[Sachse]

Yes, I've reset it a couple of times recently. It didnt get rid of the problem though.

[HiFlow5 0]

My car use to do that a lot, and I took a few steps that seemed to solve the problem.

-Made sure the TPS was set to .98 volts
-Cleaned the IAC as well as the MAF sensor
-Bought and air idle bypass plate, (goes between the TB and IAC)
-removed small vacuum cap on the vacuum T of the firewall. This got rid of an surging I had, put cap back on and it surges, take cap off and no surge.
-Then adjusted the idle to 800 rpms with the IAC unplugged and let idle for a few minutes before plugging back in.
-Dissconnect the battery for 20 minutes and reset the computer followin the reset method

That was just a brief description of what I did, hope it helped some.

[Sachse]

thanks for the help, I'll have to try those methods out.

[Mendari]

Originally Posted by HiFlow5 0

My car use to do that a lot, and I took a few steps that seemed to solve the problem.

-Made sure the TPS was set to .98 volts ...

Using HiFlow's abundant knowledge as a platform, I found this site...
http://www.allfordmustangs.com/Detailed/581.shtml
It describes setting the TPS.

Hey HiFlow,
You should try to contact Jay Leno and see if he needs an on-site Automotive Engineer.