lildemars09

Hi guys, Im going to try and keep this short but with needed info to solve my problem.

Car:94 chevy Camaro LT1 (new opti less than 700 miles on it)

PROBLEM:
while I was driving my car down the road, came to a stop and the car stall then started right up and then 200 yards it stalled out again, started it back up and made it home. next day I drove it 15 miles then it stalled and this time would not start for 5-10 minutes, made it home and kept it in driveway ever since trying to figure the issue out. I have been running it in drive way and when it gets to operating temps it stalls out. What I did was I ported intake to 58mm, just the TB port, left the ports to heads alone till I get my head and cam. I put a brand new BBK TB on intake. I am hearing a constant clicking noise coming from my air pump relay under hood. When I turn the key on once (not starting it), it clicks once, but when I go to turn key off then on again it just keeps clicking and my fuel pump stays on for a good 3 minutes +, rather than the relay clicking once while my fuel pump primes and then both shuts off. so I changed that relay out with my fog light relay and it did the same thing by constantly clicking. so that has me confused. Other than that I can not figure out why my car keeps stalling when at operation temps, something seems like its telling the PCM to shut fuel down because motor is getting to hot.

WHAT I HAVE DONE SO FAR:
replaced the IAC (I did the relearn as well), ICM, put my old coil pack on (it still stalled so I put MSD back on) cleaned MAF, replaced fuel pressure relay, fuel filter.
I did check my fuel pressure, while at idle it is running 34 PSI, then I go to hit the throttle it jumps to 42 psi. I did check the vaccum compensation and it didn't really move the PSI but I am going to verify again today. I will take it for a drive while the gauge is still on and see what kind of readings I get.

One more thing I forgot is I am not throwing any codes either, I have a guy who's going to bring me a scanner from the dealer to see if we can pull something.

If I may have left something out just mention it and I will reply with what I know. Hope many of you can narrow my search down, either to me its my fuel pump or opti.

lildemars09

Ok so a little more info. Just took it for a ride with fuel pressure hooked up and driving around it stayed at 34 PSI, WOT it jumped to 40 PSI, couldn't get on it a lot because cops around me are every where, I did the vaccum compensation off the fuel regulator (hose that connects to intake I pulled off), the gauge jumped to about 42 PSI and stayed there. The car did not stall out either while driving but I only went about a mile down the road. any suggestions what else to check? I am going to let the car sit in driveway and see if it will stall out on me and verify if what I am done so far fixed my problem but anymore suggestions will be great. Thanks guys!

Injuneer

You indicate you have no codes. How did you determine that? What scanner did you use?

Your fuel pressure sounds fine.

What brand Opti did you install? The optical cam position sensor in the Opti can heat soak. If it stops putting out the low resolution pulse signal, the PCM sets DTC 16, and shuts down the fuel system. That code does not turn on the SES light.

Can't really say anything about the clicking relays, without looking at the wiring diagrams. When the relays are clicking, what voltage does the dash gauge indicate?

lildemars09

Well I havent put a scanner on it yet. Im waiting on a guy I know to get the scanner at his dealership. My lights hasn't come up but I am going to do the scan9495 like you mentioned. I bought it from summit racing a few years ago but now they dont list it on there website. I never paid attention but if it happenes again I will keep an eye on it next time it happens.

lildemars09

In addition if I have to replace the opti... two opinions I will be taking is either selling my car and getting a LS1 and be done with the opti or i replace it with an opti delete like the efi connection 24x or another type.

Injuneer

You bought the Opti from Summit 2 years ago, but it's only been driven 700 miles?

Keep an eye on the voltage gauge.... low voltage might be causing the stalling.

lildemars09

Yea my car doesn't get driven hardly since i was busy at that time. It sat in the garage for about a year and half but I kept it started each month. I bought my car with 119k miles on it back in 09 and it just hit 125k miles.

lildemars09

What would cause the low voltage? I have noticed my rpms bobbing up and down and my lights inside car dime. When i shift it into drive the rpms drop to like 500 and my car feels like it wants to stall but I was told to adjust screw on my tb so my car wouldn't stall. But that doesnt help the bobbing of the rpms

Injuneer

Idle speed is controlled by the PCM using the idle air control valve (IAC). Do NOT adjust the throttle stop screw. You can screw up the throttle position sensor (TPS) voltage and take away the ability of the PCM to control idle RPM.

Is it possible the new IAC is bad, not installed correctly, or possibly damaged from handling?

Stock idle speed programming for the auto trans, in gear, is 550 RPM.

lildemars09

Ok well I will set it back to where it was before but how come it feels like it wants to stall out at 550rpm and my lights dime? So in park it should be to about 700 rpm? Rich now I have to set at 1000 rpm at idle. I bought the IAC from jegs. I mean this is a stupid question but how could it be installed wrong?

lildemars09

My voltage on my car 13v right in thr middle of the gauge. I got my rpms at idle in park at 650rpm I put set screw back

lildemars09

I have a video I can send u to show u what its doing. Idk how to Load it up on here unless send it to email. One more thing that I thought of but not sure why it would cause a problem beside diffferent internal dimensions, the plate that connects to the bottom of my TB, what if I put a plate from another 48 or 52 mm BBK tb on my new 58MM TB would that be the cause of all this?

Injuneer

The stock bottom plate should work fine on an aftermarket throttle body. I'm not aware of a TB that comes with a new plate. You do have to be sure you have the correct screws in the correct holes... they are different lengths, and if you put a long screw in a short hole, it isn't going to tighten and seal properly. And hopefully you used a new gasket.

Install could result in damaged pins, not seated correctly, bolts not tightened correctly, pintle damaged while attempting to adjust it, etc. Did you use Shoebox's procedure to check the continuity of the coils in the IAC:

http://shbox.com/1/iac2.jpg

First, you need to check RPM with a scanner.... the stock tach typically reads 100-200 RPM higher than actual engine RPM. Your 550 RPM in gear could be much lower. Do you have U/D pulleys? That would explain the lights dimming. But if the lights are dimming at low RPM, the volts would typically be dropping.

Many years ago, I remember the BBK throttle bodies having a problem with a "whistle" due to casting flash left in the IAC passage. Check and see if that might be a problem limiting IAC flow.

Put the old throttle body back on and see it the problem goes away. You really don't need a 58mm TB.... I was shown, with my engine on an engine dyno, that even when producing 500HP at the flywheel, a 52mm unit would have been fine. The shop laughed at my 58mm Holley.

lildemars09

Ok well I wasnt aware of the screws being different lengths so that could be a possibly and two I will put the 52mm back on and see if that will fix this problem. So far my car hasn't stalled yet but I havent driven it yet to actually see. Now this is how I relearned thr IAC, I beileve I found it on ls1tech, they said to turn thr key to on, pull the PCM BATT and PCM IGN fuse, for 5 to 10 min, then put fuses back in and turn key off.
How do I check the "whistle" problem?

lildemars09

I believe my IAC is installed incorrectly.... I just remembered that my last IAC plug port was faced upwards. How I have it now the IAC plug port is facing down towards the ground. Possibly of that causing this?