[V8] The continuing saga of the check engine light (93 4.2)

[FredParkerJr]

I had an intermittent O2 sensor failure a few years ago.  The car would run
fine for about 2 hours and then go really rich and the mileage would drop to
16 highway.  It always took about 2 hours for it to flake out - ran
perfectly fine before that.

Fred

-----Original Message-----

Subject: [V8] The continuing saga of the check engine light (93 4.2)


So, after blindly assuming that the check engine light had something to do
with the oil level, that appears to be more of a coincidence than anything
else - a strange coincidence, but a coincidence none the less.  The light
was back on in force today as milage once again plummeted into the teens
despite a recent oil change and full level.  SOOOOOOO

  Off to the mechanic.  Checked the code - oxygen sensor regulator, and
oxygen sensor out of maximum adjustment (or something to that effect...).
Mech thinks full pressure regulator sticking open, causing enrichment and
oxygen sensor unable to cope.  Ok, intake comes off and waaaaalaaaaaaa - one
of the problems - the return  fuel line is leaking (driver's back to
passenger bank, the lower hose).  So we pull all that appart and test the
fuel pressure - dead on 50.5lbs at idle, 58-59 at WOT.  Ok, so that's in
spec.  Replace the line, and light goes off.  It's stayed off for the time
being, but he's pretty sure that leaking line was NOT the cause of the CEL.

  Stumped again.  Still thinking O2 sensor?  Why am I smelling raw fuel
prior to the light coming on then, and the sensor is attempting to correct
the problem?

  Carter


W. Carter Johnson
SileStone/Counterfitt of RI
401-789-3217 home