Oil Light

On Fri, 24 Jun 2005 wrote:

['91 Sundance 2.5TBI with 202k miles, recent head gasket and valve job,
155 pounds in each cylinder, 17 lbs oil pressure at idle and 60 lbs at
4krpm, 10w30 synth w/NAPA Gold filter]

> Overall, I wonder if the sensor for the oil light is acting flaky and
> causing the oil light to come on at the wrong time.

That is the first place to focus your efforts. After awhile (and 200k
miles counts as "awhile"), the sender can go off calibration. A new one
can be had for not much money from NAPA or the dealer.

17 lbs at idle is not what you'd see with a new engine, but it's
acceptable. The suggestion to switch to 20w50 engine oil (or 15w40 heavy
duty) is probably a good one. Another possibility is that your oil
pressure relief valve is stuck midway between "open" and "closed". If
you're not getting unseemly knocking noises from the engine, and with your
excellent oil consumption and compression figures, your rods and mains are
probably fine, though at this mileage with that engine, yours would be one
of the few *not* to be setting up a hell of a racket with gudgeon pin
knock. My '92 was another of the few.

DS

I took a look at the oil pressure sending unit a day ago and saw that
it was slightly leaking oil. Later this week, I'm going to Napa to pick
up a new oil sending unit for the light.

The engine in my car was replaced over 2.5 years ago. The engine that's
in there now is a used (junkyard) engine. As far as how the engine
sounds, it makes somewhat of a ticking sound in the head at idle (which
remained even after the valve job and head gasket replacement). The
mechanics told me not to worry about it. Also, there is what appears to
be some wristpin noise (which occurs only before the engine warms up).
There's no bottom end noise as far as I can tell, though. For the last
2.5 years, I've always done my oil changes on time and used Mobil 1
full synthetic with high quality filters everytime ever since the
current engine has been in my car.

On Tue, 27 Jun 2005 wrote:

> I took a look at the oil pressure sending unit a day ago and saw that it
> was slightly leaking oil. Later this week, I'm going to Napa to pick up
> a new oil sending unit for the light.

That stands a high likelihood of solving your problem.

> The engine in my car was replaced over 2.5 years ago. The engine that's
> in there now is a used (junkyard) engine. As far as how the engine
> sounds, it makes somewhat of a ticking sound in the head at idle (which
> remained even after the valve job and head gasket replacement).

Cam followers, don't worry about it.

> some wristpin noise (which occurs only before the engine warms up)

Completely normal with this engine

> 2.5 years, I've always done my oil changes on time and used Mobil 1 full
> synthetic with high quality filters everytime ever since the current
> engine has been in my car.

Good work. If you're trying for maximum engine life, be advised you can
use the large Wix 51515 (NAPA Gold 1515) oil filter on this engine in this
car. Also make sure to keep your PCV system *in its entirety* serviced
properly; see http://tinyurl.com/yr2pg .

DS