I have this issue with my car now after the fast 92, 42lbs injectors, and I also have a tv.2 cam

I do have a tuner, he set the car up at summer time and all seemed well but once the winter came on it started bumping from 700 to 1400 back and forth, somtimes hanging at 1400.

not vacuum leaks. I do not have any tuning software myself but trying to mess with it I;

1.)waited till the car was idling at the desired 850rpm, unplugged IAC motor, still bounced when revved..

2.) I Gave it a vacuum leak, unplugged the pcv hose that pulls vacuum, Its idled smoothly at 900rpms with the IAC plugged it.

I need to go back to my tuner and have him mess with it more in the winter weather to perfect it. But I'm thinking the 42lbs injecters are in a richer tune still with cooler temps???

 

how do i get more slack (i think this may be part of the problem)? i can close the tb ever so slightly if i give a bit of a push on the cam in the right direction.

 

are the injectors scaled right? pulse widths? etc

like theyve been saying in here, timing and airflow. too high timing will make it surge, too much airflow with a 0 iac count = what i have.

 

If you just unhook the cable all together does it run any better? Which cable bracket are you using?

 

its what came with the intake.

 

SO it's the one that bolts to the first two intake bolts? If so just slot them or drill new holes depending on how much slack you need.

 

I do know he added a bunch of timing, so maybe I'll print a few posts off here for tips. I do respect the guy. My car runs 10.89 All motor with a tv2 cam, home ported ls6 heads. And gets 22 mpg on the highway. Its just the idle.

 

Mine is doing the exact same thing as the op's, and I just installed a FAST 90/NW 90 TB. Mine isn't as drastic as his but mine starts at 750 rpms cold then bumps up to 950 once the engine is warm (the IAC counts fluctuate from 0-7) once warm. What should I look into first? I retorqued the manifold bolts today and checked all the pcv/vacuum lines. There were a couple manifold bolts that were slightly loose but now they are all tight...

 

Could your iac motor be wired backwards, i believe i did this once only because i had to wire mine. Did you use new gaskets when you put the intake on. Check fitment of tb blade to bore of tb. I had to add more spring to my tb because it wouldnt pull it shut, though i run a much different tb.

 

ok, so on the recommendations of a tuner on hpt forums. it idles better but still the same kind of gremlin.

 

ok guys, its the tb cable. to others with a fast intake and hanging idle SLOT THE BRACKET

 

how many have had this issue?

 

What do you mean by slot the bracket?

 

the 2 mounting holes. they need to be elongated to put some slack in the TB cable

 

are you talking about the hole that the end of the throttle body cable actually attaches to?