The results (WAS: Differential Pressure Regulator Checking

[Ben Swann]

Tyson,

The first thing I would have done is gotten one from
rod at thepartsconnection, as it is very suspect and easy to rule out by just
replacing.

Anyway, you need an V.O.M to be working on this and any fuel injected cars
properly.  An inexpensive one is available from Harbor Freight, but you
probably don't want to wait for delivery.  So go get one from Radio Shack
or Sears.

OK, now I got that out of the way.

A rudimentary check of sensor:  resistance between the 2 pins is supposed
to be 2.5k ohms at 68 deg. F.  It will be more when colder and less when
warmer, and should drop down to around 600 ohm when engine is hot.

I did a quick check on one - it was cold out ~ 45 deg.  resistance was
about 4k ohm.  as I held the sensor part in my hand, I could see the
resistance drop.

I was checking them when the dealer wanted over $100 for one.  Now I almost
don't think it is worth it at $25 a pop.  Maybe to see if it is close or
radically out of spec.  Just clean the terminals at the connector, don't
run new wires.  The sender sits upside down on the cooling neck, which
invariably causes corrosion at bothe sender and the connector.  I have
discovered this just by wiggling the connector sometimes.

I have seen enough of these flaky thermo-senders recently in just a limited
number of cars to have submitted you this advice early on - don't wait
another week.

Ben

[Ben, we are talking about the sensor that is on the driver side of the
engine attached to a 2-sensor flange on the radiator hose, right? It is the
lower sensor.

How do I go about testing it?

If wiring is suspect and can cause this, I will run a pair of new wires to
the ECU. Which pins on the ECU do they go into?

Thanks,

Tyson]