Service Engine Soon light C4

Bob Katts wrote:
> I have a slightly loose cowl on top of the radiator (funky little rivet-
> type connector loose) that sometimes, on startup, jiggles the O2 sensor
> going into the engine from that point, according to a mechanic. Will this
> Service Engine light find its way off by itself at some point or will it
> always stay on until the battery is disconnected?

What does the O2 sensor have to do with the radiator and cowl? The O2
sensor is in the exhaust.

Bob Katts wrote:
> In article . com>
> wrote:
>
> I've been told there is a sensor between the outlet of the air cleaner
> cowl and the input of that air into the engine.
>
>
Hello Bob,

You were told right; there are multiple sensors (hot wire or pressure
and temp plus throttle position) in the intake system. They provide
data to compute the mass flow of air into the engine and enable major
adjustments to fuel injection flow rates and ignition timing.

The "oh-two" sensor isn't one of those in the intake. It looks at
oxygen content in the exhaust gas. Its output is used to optimize
fuel-air ratio -- making for better gas mileage and fewer "uglies" out
the tail pipe.

That's a frequent cause of a Check Engine light -- but, it's easier to
read the codes and make an intelligent decision before getting into
coveralls and skinning your knuckles -- that's what everyone else is
suggesting.

There are five configurations of sensors for C4s -- L98 had two, LT-1
was another, LT-4 slightly different and of course the ZR-1 was all to
it's own. When you post a question here, provide the model year and/or
engine code. That should enable a more direct answer--possibly with
better info right off the line.

HTH.. PJ
--
…PJ
’89 HookerCar, ’02 E-blu 6-spd Coupe