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Discussion Starter #1
Mike (mcola) suggested that I start a new thread as relates to the failed California smog test I recently ran on the Black Hole Spider now that it starts.

HC was 4x the limit at 507 and CO was 10X the limit at 7.4

I took the cover off of the AFM for a 'look'. Looking at the L-Jet diagnostics, it indicates that the spring on the door can be adjusted to increase fuel for a given open position of the door by turning 'gear wheel' counter clock wise but this will hurt emissions. So I intend to move the gear CW to decrease fuel for a given door position.

I noticed that the, I think, carbon contact that the copper spring arm rides on has noticeable groves where the contact rides. Is this normal or has the carbon contact been worn too much? Sorry I'm pretty sure I cannot get a good picture of this. I'll try later.
 

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But Mad North-Northwest
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Grooves are normal. AFM is far from the first thing I would check in your situation, so really suggest you put it back to the correct position so you're not messing with too many things at the same time.

First three things you should check if you're running that rich are oxygen sensor, coolant temperature sensor, and fuel pressure. Go through Greg Gordon's L-jet guide for details:

Performance Parts and Silicone Hose - HPSI Motorsports

If it's been running that rich for a while it's also likely that you're going to need a new cat converter to meet CA smog. But you need to sort out the rich running before you replace the cat.
 

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Discussion Starter #3
OK Tom, I'll go back and test CTSs again (there are two?). I went through the L-Jet diagnostics over the last year and the CTSs OHMs looked OK. I also put in a new O2 sensor before even starting the thing. Fuel pressure was tested very recently when I couldn't get it started and it was in line at 40# while cranking. The O2 sensor is a 3 wire so I'll check the heating circuit for resistance.

Bill
 

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But Mad North-Northwest
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Fuel pressure should be ~35 PSI with the vacuum hose to the fuel pressure regulator disconnected. If the hose is connected, fuel pressure should measure LESS than 35 PSI by the amount of plenum vacuum (i.e., if you're running 5 PSI of vacuum the fuel pressure should be ~30 PSI). So sounds like you may possibly have a fuel pressure regulator problem.

Check the pressure with the car running and the vacuum hose briefly disconnected, see what you get.
 

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Discussion Starter #6
This is the inside of the AFM, assuming that I can load it. The AFM has been opened at some point, that's why I took a look.

No I have not adjusted the valves.
 

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Discussion Starter #7
A couple of things I have looked at in the last couple of weeks. Larry at APE suggested I look at the O2 sensor voltage while car is running and warmed up.

I hooked a VOM up to the black wire (signal) and the voltage voltage is about 0.12 vdc while running. I tightened the spring in the AFM (CW) and observed the voltage, it would fluctuate some but would not go anywhere near the avg. 0.5 it should be. I stopped when the idle started to deteriorate.

I'm now wondering if the new O2 sensor was installed wrong or I need to replace it. Any thoughts?
 

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1st thought is you shouldn't have messed with the AFM like that; troubleshooting the AFM just requires a multimeter to measure the pins voltages and resistance. Opening the AFM was done by people looking to mod their L-Jet system...can you get it back to where it was before?

Your O2 sensor is probably bad, if that's the reading. I do know that you can't touch the tip with your fingers, or get any grease on the sensor tip when installing. Maybe that happened...
 

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Discussion Starter #10
Gubi: The fuel pressure is 30# when running.

John533i: Pin v/ohms, is that running or static? Sorry, I guess I'm in the BB penalty box for messing; a little knowledge is dangerous.
 

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Not chastising!!! I've errored on the expensive side way too often. I've replaced a starter, only to find the battery cable had perished. I have other stories that are worse...like buying a new door latch assembly for my spider, only to realize the door was locked....yeah..
 
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