Hey there fellas hear is a problem i am having for the past 3 weeks i need to get it fixed cuase i am tired of taking the bus. heres my setup quickly 350 Engine w/ a 5spd ,stock heads steel roller rockers,.424 .445 lift cam, holley 670 tbi, with 50 lb injectors , holley projection manifold,flowtech headers,1/2 inch spacer to clear the egr valve, new 350 knock sensor, esc module and finally a cop car tbi chip from Brian, My problem is my idle is really bad, first off when i start the car i can hear the iac sucking then the idle goes down, but when i drive the car for a minute or two and put it in nuetral while i am coasting the rpm fluxuciate from 1000rpms to about 1800rpms, i am totally stumped i repleced my wires, plugs, coil , cap, when i also start the car the tbi unit gets ice cold like a Co2 cartridge and stays like that for a while????THis has stumped me the only things that i can think that are my problem is my manifold is leaking (Holley projection manifold which i have heard has had problems with vaccuum leaks). my valves are not adjust properly, or when i was installing my egr valve i forgot to install the orphice thing on the bottom of my egr valve probably not a big deal but ????? and finally am getting no SES light.... PLEASE HELP I AM REALLY STUMPED AND I REALLY WANT TO GET THE CAR RUNNING RIGHT....SRY SO LENGTHY!!!

 

UHHH come on guys i thought you were experts on this TBI thing.......................................................................................

 

I am an expert on TBI (or so I'm told) but you went to someone else to do your tuning (TBIChips). So I would suggest that you either go back to your expert or learn to do PROMs yourself (highly recommended, see the DIY PROM board right here on TGO).

RBob.

 

To me it sounds like either you have a leak in your intake gasket or your vaccuum lines aren't holding up too well.

 

I had that problem when I tried to put a 300-66 Manifold on my L03, the egr (stock one) would not seal completely on the projection manifold (assuming you have the 300-66 right?) That caused a massive vacuum leak, I had fricked up idles, huge misfiring. So I went back to stock which led me to put in a crate.

If your EGR does not seat completely correct on that holley manifold, I think that is your problem because that was what caused my problems. The manifold now sits on my friends camaro and works great, but he bought an EGR block off plate from autozone. Try blocking off EGR and do the IAC reset...I strongly suggest blocking it off anyway...I'm almost sure that is your problem.