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Subject:Re: Engine Running Rich
From:John Rodgers
Date:Fri, 5 Oct 2001 14:50:45 -0500

Jay L Snyder wrote:

> I would check the fuel pressure at the tee near the regulator.  Should be
> around 29 psig.   Sometimes they get crapped up and cause higher pressure
> than they are set for, pushing more fuel through the injectors.  The ECU
> can only compensate so much in terms of injection time.  Go through the
> Bentley checklist using a multi-meter at the ECU connection.  It will tell
> you what readings you should get and indicate any shorts.  I also would
> measure the VDC coming off of your O2 sensor.  Run the engine until it is
> warm and then shut it down.  Disconnect the O2 sensor wire and read the VDC
> when the engine is running.  Should be 0.7VDC or slightly higher.  Does
> your temp gauge read OK?  Last resort would be to open up the AFM and lean
> out the spring by a few notches.  Tightening the spring will lean it out.
> Go 2 or 3 notches and drive.  At some point, it will stumble from being too
> lean.  Back up from there.  I put a new AFM on my '85 and was able to go 6
> notches leaner,if I remember correctly.  I connected the voltmeter to the
> O2 sensor wire to check the signal as I was driving down the road.  Don't
> go too lean--slightly rich makes the engine run cooler.
>
>                                                         Jay '85 Westy

A while back, someone posted a website that had pictures of the internal works
of the AFM, and described how to open clean, adjust, replace, and reseal the
unit. Great information. Is that site still available. Are the pics still
there. I's like to know for my own re-edification.

Thanks,

John Rodgers
88 GL Driver