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914World.com _ 914World Garage _ oil pressure light on

Posted by: Rocket Mar 16 2006, 04:18 PM

ok guys,

i was out with my dad in my car today and the oil presser light on the dash went on. he says thatit dosnt sound like theres low oil pressure so he told me to look up a test online to see if the oil pressure sender was faulty. i looked it up here and i couldnt find a test.

is the only test take it out and put another one in and see if it works?

'74, 1.8l

-rocket

Posted by: lapuwali Mar 16 2006, 04:23 PM

Get a handheld mechanical gauge with a 1/8" NPT fitting. Remove the stock sender, start the engine, check the oil pressure. That's how you test.

By the time an engine with low oil pressure makes noise, you're ready to rebuild it, anyway. The damage has already been done.

Posted by: Rocket Mar 16 2006, 04:24 PM

is there any test to do with a volt/ohm meter? cause it might be electrical. and does it go through that logic switch underneath the passenger seat?

Posted by: ClayPerrine Mar 16 2006, 04:28 PM

QUOTE (Rocket @ Mar 16 2006, 04:24 PM)
is there any test to do with a volt/ohm meter? cause it might be electrical. and does it go through that logic switch underneath the passenger seat?

The oil pressure switch is closed when there is no oil pressure. Pull the green wire from the switch and see if the light goes out. If it doesn't, then you have a short in the wiring.

I would still check it with a mechanical gauge.

And no, the oil pressure light does not go through the big brother relay under the passenger seat.

Posted by: Rocket Mar 16 2006, 04:31 PM

alright, well its off when i pull the plug, so im oging to replace it and see if it stays off....

ill keep ya posted

Posted by: bd1308 Mar 16 2006, 04:33 PM

uh, when you put that new sender in there....make sure its tight but not too tight.

I leaked about a quart of oil PER day and it was from a leaky oil pressure sender.

these cars are great, arent they

b

Posted by: ClayPerrine Mar 16 2006, 04:45 PM

QUOTE (Rocket @ Mar 16 2006, 04:31 PM)
alright, well its off when i pull the plug, so im oging to replace it and see if it stays off....

ill keep ya posted

PUT A MECHANICAL GAUGE ON IT!!

Posted by: Cap'n Krusty Mar 16 2006, 04:57 PM

QUOTE (Rocket @ Mar 16 2006, 02:31 PM)
alright, well its off when i pull the plug, so im oging to replace it and see if it stays off....

ill keep ya posted

DO NOT buy the generic FLAPS sensor! They're cr*p, and often won't even go in the hole in the tin. VW # 021 919 081, avaqqilable at most foreign car parts stores, Porsche and VW shops. Should be 6-7 bucks. 24 mm deep socket to change it. Oh, and make sure you have enough oil in the engine! The Cap'n

Posted by: r_towle Mar 16 2006, 07:03 PM

it was loose
so no ground...tighten it down and all set.

R

Posted by: ejm Mar 16 2006, 08:25 PM

QUOTE
And no, the oil pressure light does not go through the big brother relay under the passenger seat.

Technically the oil light wiring doesn't go through the seat belt relay but the wiring does make a stop there at terminal "B". A relay that's not securely mounted or has water in it could cause a false oil warning light.

Posted by: r_towle Mar 16 2006, 09:10 PM

QUOTE (ejm @ Mar 16 2006, 09:25 PM)

QUOTE
And no, the oil pressure light does not go through the big brother relay under the passenger seat.

Technically the oil light wiring doesn't go through the seat belt relay but the wiring does make a stop there at terminal "B". A relay that's not securely mounted or has water in it could cause a false oil warning light.

I know it goes through there...we already disected that wiring online here...

Can I just take it off of that relay "logic circuit" and wire it to the lead that goes to the light, or ???

Why is it going through the logic circuit?

I would like to eliminate that logic circuit completely, this is the one thing that I would like to retain, I would like to keep the oil pressure light working correctly...

Rich

Posted by: Joe Ricard Mar 16 2006, 09:44 PM

Whoa Whoa Whoa.
you said the light stays off when you pull the wire.

DUh because you eliminated the opportunity to be grounded through the switch.
Your switch is doing it's job as you know. turn key light goes on fire up engine light stays on for more than a half second YOU GOT A PROBLEM and a very expensive one (no oil pressure).

Bite the bullet and get a mechanical gauge If you think it's too expensive ask what a rebuild costs..

Have you checked the oil level in the sump? is it the correct viscosity might it be diluted with gas or water?