Date: Tue, 18 Feb 2003 08:30:26 -0800
Reply-To: van man <vannman99@YAHOO.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: van man <vannman99@YAHOO.COM>
Subject: Running Rich - O2 sensor reading low?
Content-Type: text/plain; charset=us-ascii
Hi,
I think I have been running rich for a while, at least
I have noticed about a 2mpg decrease in fuel
efficiency. Things got bad on a road trip a few weeks
ago - I lost all power going up a grade and the van
was idling VERY rough. I shut off the engine, turned
it back on(resetting the computer), and it was fine.
This started to happen with increased frequency on the
road trip, ONLY ON GRADES, so I disconnected the O2
sensor and she ran great, seemingly with more power
than I had remembered in a while.
I have been driving around town for a week with the O2
disconnected, and I seem to be getting better mileage.
I had a new O2 laying around, so I spliced her in this
weekend, and while I haven't tested it on a grade yet,
I brought the digitool out to check some readings. It
seems as if the O2 is detecting a lean mixture(?).
When I first turn on the van, the digitool reads about
.6-.75. However, as soon as I give it any gas, the
reading drops, and as I drive, it will hover between
.15 and .35. As soon as I let off the gas, it goes
negative to about -.5, then once idling again, its
back to .45 - .55 (when warm).
The other readings seem ok, I think...
AFM is 1.5 -1.65 at idle, 3.5 at 3k RPM - but never
higher, even when its floored - should it be higher
when its wide open??
Temp I - 1.68ish when warm
Temp II - .14 when warm.
Throttle switch is sticky when I first start it up,
but seems great after a minute or two.
I guess my question is what could cause a new O2
sensor to read so low? I have taken extra care to
make sure the ground on the green wire isnt touching
the female connector or grounding out anywhere.
Im a little suspicous of my cat converter... if it has
failed, could it be messing with the O2 sensor? I
have a new cat, but am hesitant to swap it out for
fear of blowing it if I continue to run rich.
Thanks!
Jeff
__________________________________________________
Do you Yahoo!?
Yahoo! Shopping - Send Flowers for Valentine's Day
http://shopping.yahoo.com
|