Oil light intermittently off before start up

[VWbusChick]

I've noticed that occasionally, our oil light doesn't come on along with the other 2 indicator lights when powering on the bus (turning key to on position, but before start-up). Usually when I turn the key to the on position before starting, all 3 dashboard indicator lights illuminate. But every so often, the oil light fails to light before start-up. This occasionally results in a hard start, but not always. Any ideas on what this means? It's a 1978 bus with original 2000cc fuel-injected engine.

[dtrumbo]

I'd check the following:

Make sure the oil pressure indicator bulb is secure in its socket (bulb holder). In addition, make sure the socket is securely installed in the instrument panel (not super-easy to wiggle around) and the wire attached to the socket is not loose or corroded.

If that doesn't reveal any smoking-gun, check the connection to the oil pressure sender on the engine. As with all electrical connections, make sure they are clean and fit nice and snug!

This is kind of a long-shot, but make sure fuse #12 is in its socket with no corrosion on the spring-terminals. "Rolling" them around while in the socket can sometimes create a better connection. Fuse #12 affects your other indicator lights in your instrument cluster so I doubt this could be the cause.

I can't see how only the oil pressure light not coming on at ignition-on, while all the other lights behave correctly, could be the cause of your hard-starting problem unless there are some VERY strange things going on. Did the two symptoms appear simultaneously or has one been going on longer than the other. Check everything out and get back to us!

[Amskeptic]

As per the post above + it is common for the intermittant light on-off symptoms you describe. Dirty oil can contaminate the electrical contacts within the oil pressure sender, and there is no field repair to clean them up. If you replace the sender, recommended, please get a VW Audi sender. Don't waste time with aftermarket crap that weeps and dirties up the entire engine with oil induced grime.
Colin

[khargis]

78 bus runnin solid, but on the way back from bend to portland, or. my oil light was flickering kinda on, but really dim. pulled over and checked oil, which i did befor leaving and all was fine. did not seem to affect driving, but when i would come to a stop or better yet, take my foot of accelerator, the light would grow brighter. i read the above postings, are these things i should check as well? thanks, kris

[Gypsie]

Don't waste time with aftermarket crap that weeps and dirties up the entire engine with oil induced grime.
Colin

What he said...

Khargis, you may have an actual oil pressure issue rather than a faulty connection/sensor issue.

Flickering under running rpms and load...? Hmmmm. does is do it at start up, during the first ten minutes of driving or after a full on hot run...?

When it does it at idle, will it go away with a slight rpm increase?

First go through and assure all the above mentioned connections are addressed. If it is still present, I would start to think "reduced pressure from increased clearance" (specially if it waits till everything is fully thermally expanded) or "oil pump" (either increaded clearance (more likely or gummered up (not likely).

2 cents with change expected.

[khargis]

hey gypsie. yes the light will go away with slight rpm increase. it just started doing it yesterday on my way home, so i will observe today. i will check all connections and familiarize myself with the oil pressure sender. is it way bad to drive right now?

[khargis]

fixed it! the wire that goes to sensor was shortin out by restin on the engine block, so i insulated it and secured, no more light! yay!

[Gypsie]

=D> niiice....

connection issue after all. good to know.