Oil pressure light,1991 240 manual 5 speed

[skinksrus]

My oil pressure light flickers on and off while idling at a stop sign (not all the time). This has been an ongoing item for +/- 10 years. I had a mechanic look at it and he indicated that the engine wasn't getting enough oxygen at idle for the pressure required. The car sounds just fine at idle even when the light flickers. Is this really a problem or should I just consider it a loose wire or something far less serious than the oil pressure pump?
Thank you.

[billofdurham]

(not all the time).

Does it do this when the engine is hot or cold or does it not make much difference?

The last time I had similar trouble was on my old 240 and we found that the idle speed was about 100 rpm too low.

If it has been doing this for 10 years why have you queried it now? Is it getting worse?

Bill.

[skinksrus]

It does not matter if the engine is hot or cold. Just an occasional flicker of the panel light. I am only questioning this now as my mechanic brought it up to me but when I informed him that it has been doing this (and running fine) for 10 years he was a bit baffled as well. The car does not sputter or conk out at idle--it just sounds like a sewing machine. When the light flickers if I give it some gas the light will go away.

[billofdurham]

A baffled mechanic, how strange!

Two things to check:

1. Idle speed should be about 800rpm on automatic box or 900rpm on manual. What does yours show on the rev counter? Bear in mind the rev counter is only a guide and not totally accurate but it should be close enough.

2. Your car should be fitted with a self diagnostic box. Have fault codes been read from this? If you aren't sure about the procedure I posted a full how-to on:

https://www.matthewsvolvosite.com/chat/p ... php?t=9708

Go to page 2 and scroll down. It is headed as 740 but it also applies to your year 240.

Bill.