suzukirmzrider

I am working on my sand car that has a 2.4 LE5 from a 2006 Cobalt SS. It has a 105 amp alternator on it from basically a 2005 cavalier, 2008 cobalt injectors, 2008 cobalt MAP sensor, running in speed density, and all other sensors are stock to the 2006 cobalt ss 2.4 LE5. It has an aftermarket air intake system (UMP offroad intake), header with no restriction, AEM fuel pump and Aeromotive fuel regulator set at 55psi idle. I have dual 14" SPAL fans on the radiator that are controlled by ECM.

I am having trouble with my tune. The problems are:

1) Idle surge. It will idle great for a while, then it will stumble and start idling bad, hunting up and down. The motor pulls hard off of idle.

2) Once fans kick on at set temperature in the ECM, the will not shut off. They continue to stay on as long as the car is still running. It will pull coolant temps below 100 degrees F!

This car was ran with a MEFI system, but I am so far away from MEFI tuners, I decided to go with a stock computer with VATS removed to run in stand alone. Since it ran great with the MEFI system, I have a hard time believing anything is wrong mechanically, and am confident it is in my tune. There are only a few things it could be: Crank Position Sensor, Knock Position Sensor, Throttle Body, Pedal, or the Tune itself. These are the only things that have changed since the car ran great on the MEFI tune.

I have been using HP Tuners, so I will attach my files for anyone that can view them. ANY help or input would be GREATLY appreciated!! Thank you in advance.

I did forget to copy High Octane table from MAF to the Low Octane table for Speed Density tune.

eee file is near WOT run
06cobaltBuggy Kramer revF.hpt

06 Cobalt idle issue.hpl

06 Cobalt idle issue eee.hpl

Sl0wbaltSS

Is the correct ECU in the car?

suzukirmzrider

Yes. It is an E67 computer from a 2006 Cobalt SS 2.4 LE5.