Hi dfeary!
my 2001 Outback went through DC DMV vehicle test yesterday, and the
check engine light was off when it went in and on when it came out -
I'm assuming that it has something to do with the emissions testing?
Anyone know whether it is likely to go off on its own, or is this going
to be an expensive service trip?
Thanks
Mmmmm, you're not gonna like what I'm about to tell you, BUT . . .
My sister was in a depressingly familiar sounding fix recently; CEL
immediately following a visit to a local service shop for a routine
oil change on her '96 Legacy.
I borrowed an OBDC reader from a friend, and when plugged in, it spit
out a "cam sensor" fault. Further investigation found that the plug on
top of the cam sensor was loose (as in just sitting on the sensor, not
"clicked" into place). Odd, because I was the last person to service
the engine, and while it is entirely possible that I might not have
gotten the connector all of the way on, it seems highly unlikely that
the car would have traveled over 10K miles of bumps and ruts without
it triggering a CEL if I had done so. Added to the fact that the cam
sensor is readily accessible on the top of the engine, and you begin
to see where I'm going with this. (Novel way to drum up service
business, and an easy fix, too!)
FWIW, emissions testing involves putting a probe in the exhaust, a
magnetic pickup near a plug wire, and running the engine up to a
certain RPM while monitoring the exhaust gas, nothing more, and
absolutely nothing that would cause a CEL to magically appear.
But then I have a nasty, suspicious mind . . .
Check any accessible electrical connections (Cam sensor, crank sensor,
knock sensor, O2 sensor, TPS, temperature senders, etc) to be sure
they are good, disconnect the battery for a couple minutes to clear
the CEL, and see if that doesn't help. If the CEL persists, it is just
possible that something failed simultaneously to the emissions test
being performed. Possible, but unlikely
ByeBye! S.
Steve Jernigan KG0MB
Laboratory Manager
Microelectronics Research
University of Colorado
(719) 262-3101