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Discussion Starter #1
autozone finally found a code for my CEL. Got a 41. Lean engine. I figured that may be the problem since my plugs were white. Their computer suggests o2 sensor or fuel filter. I don't believe its the sensors since the plugs agree with the lean code.

I have an adjustable regulator set at 38 psi. Should I raise the FP, get a filter, or both? Any other culprits?

suggestions please.
 

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Code 41 is one of two things...It could be that the O2 sensors are not "switching", which would mean they are dead. When they don't fluctuate, they usually stay at low, or no voltage, which tells the PCM that the car is too lean. This will usually give you a bad idle, and very erratic low rpm driveability....

The other thing Code 41 could be is that the "system" is always lean. I got this code on my 94 GT shortly after I installed a C&L meter. At light throttle cruise (like on the highway), the car was too lean. I see you have one also. A Pro-M Bullet meter cured my LEAN code, and the car has been fine ever since...

To verify if the O2's are dead, use a DVOM (digital multi-meter) set on VOLTS, and back probe the PCM harness where it plugs into the PCM, at PIN # 43 (for the left sensor), OR 29 (for the right one). I'd check both. With the car warmed up, and at idle, or when revving the engine slightly, the voltage readings should be fluctuating rapidly. If it isn't, the O2's are bad and need to be replaced.

If they are working properly, I'd try another "known good" meter (preferably a Pro-M)...
 

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Discussion Starter #3
I read that bad o2 sensors would cause your car to overcompensate and actually run rich. My plugs are white instead of tan. I must be running lean.

I've heard the same thing about C&L MAFs. The only other MAF I have available is the stock 19# MAF. What would happen if I "tested" it for a while w/ my 30# injectors. I'd run rich, wouldn't I?

I don't want to buy a new MAF as a guess.
 

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No, I wouldn't just go buy one either, without being at least somewhat sure that is the culprit. That's why I suggested trying one that's "known" to be good, as in a loaner from someone local. If that's not an option, it doesn't give you many alternatives...

A stock meter with 30's would run way too rich, probably too rich to even run anywhere near right...
 
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