1997 Chevy Cavalier 4 cyl Front Wheel Drive Automatic 150K miles
This is an extremely well maintained car. Even at this age, it has no sludge in oil and is not using/leaking oil. Some time ago, the oil pressure warning light started coming on at warm idle. I had someone check the pressure. Guy stated it was 7 at idle and 70 at 3K (or 3.5K) rpm's. It wasn't the kind of shop I wanted to actually replace the oil pump so I took it to someone else for that. That mechanic stated that the oil sending unit "looked new" and didn't replace it. I had previously informed him that the sending unit had been replaced at around 100K, so clearly it wasn't new. At any rate, he did replace the oil pump (though he later stated it looked to be in really good condition, too!) At my request, he also changed the screen while he was replacing the oil pump.
Nevertheless, the oil pressure warning light STILL comes on at warm idle. I called the mechanic who replaced the oil pump and asked him did he check the oil pressure manually before I picked it up. He stated he didn't because he doesn't own a manual gauge. (Oddly, over 50% of the shops I've called today also do NOT have manual oil pressure gauges. What is up with THAT? Oil is the lifeblood of the car - how can you have a shop and NOT have something to check the oil pressure?) THe oil looks good. No foaming, no odd color, and it appears clean. There is no notable engine noise - I'm not hearing anything from the lifters or rods.
But here's something else of interest that I had previously ignored. The seat belt warning light (which is located directly above the oil press warning light on the instrument panel) also has a tendency to come on/blink when braking and then stopping the car, and goes off shortly after moving/accelerating again. About 80% of the time both lights appear to be coming on in tandem. I previously ignored this, because I was completely traumatized by the thought of low oil pressure anywhere in my engine. I wanted to focus on that and be sure THAT problem got resolved. Of course- it's NOT.
As soon as I can find a local shop that actually HAS a manual check gauge - I'm going to have someone manually check the oil pressure again. The car has a WARM idle speed of 600 to 700 rpm's. (1,000 to 1,100 at cold idle). Since it's winter, I'm not inclined to change the oil to a heavier weight. I don't want to starve my engine on some really cold morning. Any thoughts on what is actually going on here?
Much appreciated, Wendy
have the same problem?
Sunday, January 6th, 2008 AT 8:00 PM