# oil Light on 02 jetta 1.8t.



## mericw (Apr 26, 2004)

About 8 months ago my oil light came on for the first time. I thought it was because i was overdue for a change. Changed the oil and everyhting was fine for some time.
Usially the light would turn come on and i would push the clutch in to drop the RPM and it would go off and stay off.
One day i was driving home (85 mile commute each way) and the light came on and stayed on, engine started to run funny so i shut it off and brought it to a garage. the car sat for 2 days then they tested the pressure and said it was fine. They replaced the sensor thinking it was that.
Drove the car for a few months and a couple of oil changed with no light. Then it came back. Founds that i had about a cup and a half of oil in my intercooler and the turbo had been making noises lately. Figured i blew the turbo and that was causing my oil issue. So i repleced the Turbo with a K04 and dropped the oil pan to check for sludge. Pan was clean but the screen was a mess, so i replaced it.
Now 3 week later with no oil light it came on for a second last night. What would cause this issue to only surface every now and then and go away if the car sites for a couple days?


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## mericw (Apr 26, 2004)

bump??


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## mericw (Apr 26, 2004)

Everybody just thinking sludge. Any other opinion would help.


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## animaniac (May 26, 2005)

*Re: (mericw)*

With the sender replaced it's either intermitant low pressure, or break or loose contact in the sender wire.
If the engines sludged you would get the oil light if the sludge blocked the pick up screen, if the oil pump is worn again you will get the oil light if it drops low enough, the light should only come on when rpms are above 2k, hense whats why your light goes out when revs drop.
If the oil pressure has been tested then your problem lies with a faulty sender connection / wire.
If you disconnect the wire and hold revs above 2k the oil light will come on.
What you could do is get an oil pressure gauge, or more simple if you dont want to fix gauges anywhere is get another pressure sender and an adaptor so you can have 2 pressure senders screwed into the oil filter housing as i'm unsure if there are spare holes in it.
And an led any 12v led, wire it up to 12v positive and the negative wire to sender, and if the engines got oil pressure the led remains on, when the pressure drops the led goes off.
So when the oil light comes on again, your led will give a 2nd true reading of what going on, if the oil light comes on yet the led is on you know the oil light isnt giving a true reading, but if the led goes off when the oil light and buzzer starts beeping you know to shut the engine down.


_Modified by animaniac at 6:49 PM 8-19-2009_


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## mericw (Apr 26, 2004)

The car has 158k on it, how would i know if the problem kies with the oil pump starting to fail? what typically happens when the pump starts to go?


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## animaniac (May 26, 2005)

*Re: (mericw)*

You will get low oil pressure, according to haynes manual quote ''slightly lower oil pressure at idle in a high mileage engine isnt a cause for concern, whats is, is lower oil pressure at higher rpms'' vw's is a 1.8 bar switch, so the pressure has to drop below that to trigger the light.
If the oil pressure has been tested i really wouldnt have thought that the oil pump is worn and is intermitantly producing lower pressure, because the pump is just a few cogs which turn.
I soppose if you want peace of mind just buy a new pump.


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