Race car won't idle. A lot of troubleshooting done, need experts! - Maintenance and Repair Forum

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Race car won't idle. A lot of troubleshooting done, need experts!
Thursday, August 21, 2014 6:07 PM
I had a whole long post written up, and my session timed out so here's the sort and sweet version We bought an old racecar to do 24 Hours of Lemons, and so far it is living up to it's name.
1997 Cavalier 2.2 OHV 5 speed gutted and caged
Jaz fuel cell and sender with external fuel filter and pump wired to a switch, no PCM control.
Short ram intake connected to valve cover hole with K&N filter
4-2-1 exhaust header with O2 sensor to glasspack and turndown tip. No post-cat O2 sensor.
All emissions equipment removed and vacuum lines plugged, except FPR and PCV.

The car will crank and quickly fire up, but won't hold idle, stumbles, and dies if I don't modulate the throttle. If I go WOT, it dies. Modulating the throttle it will barely run for a while, stabilize to a high idle for a few seconds, then stumble and barely run again. I'm not getting a CEL or any pending codes. After it dies it smells rich and the spark plugs are a dry black.

Here's what I've replaced:
Fuel pressure regulator
Crankshaft Position Sensor
spark plugs

Here's what has tested good:
TPS
MAP
IAT
IACV (motor and signal from PCM)
coolant temp sensor

Here's what I've cleaned:
IACV
K&N filter
Fuel injectors and screens with O-rings removed in an ultrasonic bath of TB cleaner for about an hour.
PCV

My questions:
The oil pressure sensor has been removed to connect a gauge. Could this cause a problem with the PCM?
With the engine off my scangauge reads 6 degrees of ignition advance, and then when "running" no more than 20, usually in the low teens. Is that too low and possibly the ICM?
It sounds really lopey while I'm working the throttle, like a harley or a 350 with a cam. Could this be a bad coil or ICM? All 4 exhaust runners are getting hot.

Please ask me anything, as I 'm sure I'm missing some details.
Thanks in advance for helping a J-body newb!

Re: Race car won't idle. A lot of troubleshooting done, need experts!
Sunday, August 24, 2014 12:11 AM
From what i'm reading I think all youre problems may be in youre fuel cell set-up because the pcm needs to see that 5v reference from the FTP sensor and 5v reference from the fuel pump, the stock pcm is going to be thown off not seeing those references. Is this un-tuned pcm?


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Re: Race car won't idle. A lot of troubleshooting done, need experts!
Thursday, September 04, 2014 1:22 PM
I'll take a look at that, I know that there's no FTP sensor on the fuel cell. As far as I know it's a stock PCM. We did a compression test and got 130-140-130-130 at 5500ft elevation. I'm thinking that unmetered fuel is getting into the combustion chamber either through leaky injectors or bad seals and flooding several cylinders. Is there any trick to installing the injectors?
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