50+ STFT at idle?

[geo53PSI]

I tried changing the injector data once, but as soon as I saw that it did not make much of a difference I reverted back to the original data for the 25lb injectors.

Tried tuning the VE table with the original injector data and got it to idle smooth and rev up good. However, the VE table looked ridiculously wrong. At 15KPA and 1600RPM cell it's already at 102 on the VE table

This leads me to believe it's very small injectors that are on the truck compared to the data, or there is a very big leak somewhere in the intake.

Needless, to say we are ordering another set of injectors, (seller says these will be the proper 25lb injectors it should have) and checking all of the intake for cracks, breaks and leaks.

Thanks for all the help to everyone that has replied, I will keep this thread updated on what we find.

[2xLS1]

If you are buying injectors why buy such small ones?

[schpenxel]

True.. though if you're never going to need more than they will handle then they'll work just fine

[geo53PSI]

Truck is just going to be a weekend driver.. dont want anything other than what it already has...pretty much stock other than a cone intake and headers...

[2xLS1]

Are you trying to tune this with open headers?

[schpenxel]

That would represent a slight problem if so.

[geo53PSI]

it is not open header, it has dual chamber exhaust with side dumps

[2doorimpala]

Check for intake manifold gasket leaks.

[geo53PSI]

First off, thanks to everybody on here that presented useful information.

Just want to update the thread and let everyone know what the issue was.

1) Found a penny size hole 4 inches behind the MAF / Fixed it

2) Changed out the intake gasket, looked okay but one spot was questionable where the gasket was a bit distorted.

3) Got new correct/injectors from a reliable source

Fired up with no issues.

Adjusted stoichiometry, disabled/removed COT codes, adjusted fans (we have 115* weather here daily), adjusted idle rpm, a bit of timing tuning (these trucks leave alot on the timing tables), Hot /Cold Pedal for PE, PE EQ

Got it to 180 and started logging for trims correction. Trims were at bout +/- 5%

Went back and massaged the VE table along with a bit of tweaking to the MAF curve to compensate for the headers and CAI.

Write calibration

Fuel trims all within 1%

Attachment 60564


Very happy to have gotten this one solved! Hope some of the info on here will help others.

[schpenxel]

Good deal!