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Subject:Re: Thirsty motor with low power to 2,500 rpms. What's up?
From:Greg Potts
Date:Sun, 18 Oct 2009 20:17:22 -0400

Hi Chris,

I checked fuel pressure yesterday, it sits at 30PSI at idle but jumps to
40 as throttle is applied and then settles to 30 again as soon as the
revs catch up to the throttle. I also checked the vacuum lines and found
the two going to the vacuum can on the gas tank vent unit were
unplugged. Fixing that didn't help.

Tried swapping to a spare AFM, it made no difference to performance.
Tried a different ECU, same deal. If anything it got worse.

Then I tried unplugging the O2 sensor; It was like I bought a whole new
engine. The 1000rpm torque hole is gone. Highwat performance is alsoi
improved. It's a lot more drivable now that I don't have to take it to
2K or better before I let out the clutch. It'll be interesting to see if
the milage improves.

What's the life expectancy of an O2 sensor? This one might have 20,000
miles on it.

Happy Trails,

Greg Potts
1973/74/79 Westfakia "Bob the Tomato"
1987 Wolfsburg Weekender Hardtop
www.busesofthecorn.com
www.pottsfamily.ca

Chris S wrote:
> Greg,
>
> Sounds like you covered your bases well.  Any idea what the fuel pressure
> regulator is doing?  The AFM track check is a good idea too.
> \