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Sun Mar 21, 2010 9:17 pm

My oil pressure buzzer is still going off when it gets below 2400 RPM'S after the engine has warmed up. It seems too precise for it to be a faulty wire and it has done it since it was purchased in 2002. The engine itself has never run better.... I still need to change those fuel lines though :oops:

Sun Mar 21, 2010 9:22 pm

have you checked the oil pressure?

Sun Mar 21, 2010 9:38 pm

Wouldn't signs of low oil pressure be burning,leaking, made valve seals? My van leaks no oil it is pretty amazing. It rarely burns it as well (I've never seen it burn oil actually). I better knock on some wood all this talking about my engine running fine might actually make it explode in the near future. The van has been driven around the entire midwest as well the buzzer noise going along for the ride as well, this was in 2002.

Sun Mar 21, 2010 9:58 pm

There are 2 different sender units for the later vans that are for oil pressure. One is for high rpm and the other is for low rpm. You might have a bad sender or loose wire possibly even a tired motor. I would assume it is one of the first 2 options though. http://www.van-cafe.com/home/van/page_15_9/oil_pressure_problems.html

Sun Mar 21, 2010 10:00 pm

just what I needed syncrodoka thanks!

Sun Mar 21, 2010 10:14 pm

Bruskyvw wrote: Wouldn't signs of low oil pressure be burning,leaking, made valve seals?

I dont think any of those symptoms will indicate low oil pressure. Your oil pump could be worn out and at the same time not exhibit any of the above symptoms. Check your sensors though. that is cheaper.

Mon Mar 22, 2010 8:53 am

wgargan wrote: have you checked the oil pressure?

This symptom comes up often here on Samba. While the switches, wiring, and the dynamic buzzer could be at fault. You should always verify what the oil pressure truely is when the buzzer is on. The buzzer was a built in design to warn you of "too low" oil pressure before there was "no" oil pressure.

Quote: Wouldn't signs of low oil pressure be burning,leaking, made valve seals?
No the symptoms of low oil pressure would be the warning buzzer going off. The symptoms you describe would be for an engine that was using oil. 8 years is a long time to run with the warning buzzer going off.

Mon Mar 22, 2010 9:22 am

A very possible cause is the wrong oil pressure switch in position #2. Many places once listed the wrong pressure range switch for this and if someone installs the wrong one it makes the alarm sometimes go off just above 2000 rpm. The #2 switch is ignored by the oil warning logic below about 2000 and much above that rpm the pressure is high enough to work even with the wrong switch.

Even the Vanagon Bentley has the wrong pressure switch shown on some diagrams. Compare page 97.91 bottom track 47 with page 97.108 bottom track 47. The first page is 1986, says switch is 1.8 bar, the second page is 1987 says switch is 0.9 bar. The second page is right for all 2.1, should all be 0.9 bar for the #2 switch. Then it gets it wrong again for 1988/89 and 1990, pages 97.126 bottom track 50 says 1.8 bar and 0.9 bar!! and page 97.208 bottom track 50, says 1.8 bar. These should all say 0.9 bar.

Mark

Bruskyvw wrote: My oil pressure buzzer is still going off when it gets below 2400 RPM'S after the engine has warmed up. It seems too precise for it to be a faulty wire and it has done it since it was purchased in 2002. The engine itself has never run better.... I still need to change those fuel lines though :oops:

Mon Mar 22, 2010 9:46 am

Since mine is a 1991 I'm assuming I might need a 0.9 bar..correct?

Mon Mar 22, 2010 9:50 am

Sounds like a logic problem to me. Even with a bad or incorrect pressure switch installed, you would think that the buzzer would go off when the RPM increased above the 2000 rpm set point not when it dropped below a 2400 rpm set point.

Does the buzzer stay on once the rpm's drop below 2000? It should never come on below 2000 no matter which pressure switch is installed.

Mon Mar 22, 2010 9:51 am

All 1986-1991 with 2.1 should have the 0.9 bar switch in position #2 (and 0.3 bar in position #1)

Mark

Bruskyvw wrote: Since mine is a 1991 I'm assuming I might need a 0.9 bar..correct?

Mon Mar 22, 2010 10:03 am

When the oil is cold and thick the pressure is often high enough even for the wrong or bad switch to work. Once it thins out from heat during a drive it will be fine until the rpms get down low enough for the pressure to drop and trigger the switch. People with Vanagons have been fighting this wrong switch problem for 15 years that I know of, because the wrong part has been listed in various places. Even the VW dealers fitted the wrong ones at times.

Mark

Wildthings wrote: Sounds like a logic problem to me. Even with a bad or incorrect pressure switch installed, you would think that the buzzer would go off when the RPM increased above the 200rpm set point not when it dropped below a 2400 rpm set point.

Does the buzzer stay on once the rpm's drop below 2000? It should never come on below 2000 no matter which pressure switch is installed.