# Oil Light on S4



## S4Neil (Oct 22, 2007)

My oil light comes on occasionally even though there is no drop in oil levels. It seems to come on when I take a winding corner on off ramps). The dealer says that a drop in pressure is causing it and after they measured found that my oil psi at idle is 17.0 when it should be between 17.6 and 2.3; and at 2000 RPM it is at 32 which is above the minimum of 29 PSI. They say replace the oil pump but another specialist says that this is a common problem caused by sludge in the lines and that the pump is just properly detecting the sludge. Clear out the sludge and the oil light will go out. Who do I believe?


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## hyperformancevw (Mar 15, 2007)

*Re: Oil Light on S4 (S4Neil)*

if the pressure is within spec mechanically i would think the pressure ensor itself was the problem. there is nothing wrong with the oil pump if it is capable of 17 psi at idle.


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## S4Neil (Oct 22, 2007)

Thanks for the reply. I tend to agree with you. Probably just sludge here and there


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## hyperformancevw (Mar 15, 2007)

*Re: (S4Neil)*

yea i would try to relpace the sensor first. it is worth a shot for the price. you tested it with a mechanical gauge so there is definitely nothing wrong with the engine or pump. you also might want to try an engine flush. some repair shops offer it. if you are concerned with sludge, you can always pull off a valve cover to see how it looks inside. http://****************.com/smile/emthup.gif


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## buddylee401 (Oct 24, 2007)

*Re: (hyperformancevw)*

if you're gonna pull the valve covers off, do yourself a favor and pull some of the center camshaft caps off. if they look like they're scored, you may not have good oil circulation through the tops of the heads. poor oil circulation through the tops of the heads is usually caused from blockages in the pcv system. (that was part of the 1.8t engine replacement/oil pump replacement debacle.) the only reason why i suggest pcv, is because you said your actual oil pressure is good, so we know it's not the pump itself.
if you wanted, you could pull the oil pan, and clean the screen in the pump pickup.
when you take the y pipe out (to access the valve covers) do your best not the snap the valve on the driver side, back by the secondary air pump. we here at the dealer break them all the time. depending on the year of your car, you may not have secondary air. if that's the case, the valve i'm talking about has 4 vacuum ports, if you have secondary air, it only has 3 ports, and is kinda a "Y" shape.


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## S4Neil (Oct 22, 2007)

Thanks guys for all the advice. It really doesn't sound like I need a pump. I am bringing the car in again for another oil leak around one of the cam seal plugs and then reassess.


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## bluelagoon1 (Apr 21, 2005)

*Re: (buddylee401)*


_Quote, originally posted by *buddylee401* »_if you're gonna pull the valve covers off, do yourself a favor and pull some of the center camshaft caps off. if they look like they're scored, you may not have good oil circulation through the tops of the heads. poor oil circulation through the tops of the heads is usually caused from blockages in the pcv system. (that was part of the 1.8t engine replacement/oil pump replacement debacle.) the only reason why i suggest pcv, is because you said your actual oil pressure is good, so we know it's not the pump itself.
if you wanted, you could pull the oil pan, and clean the screen in the pump pickup.
when you take the y pipe out (to access the valve covers) do your best not the snap the valve on the driver side, back by the secondary air pump. we here at the dealer break them all the time. depending on the year of your car, you may not have secondary air. if that's the case, the valve i'm talking about has 4 vacuum ports, if you have secondary air, it only has 3 ports, and is kinda a "Y" shape.

going from this info, i finished my stage 3 a week ago, and its got about 800mi on it. after pressure testing it last night, it began to blow a ton of smoke out the exhaust, and it was definitely oil. it was dripping out of the flex pipes on the downpipes at one point right after pressure testing. i'm guessing that when we pressurized to intake, the pcv check valve took a poop and not its letting a great amount of oil from the crankcase and putting it in the intake system all the way through the exhaust. what's the solution? is it a new pcv sytem that i need for the extra boost pressure or just a new valve?


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## 2035cc16v (May 18, 2000)

*Re: (bluelagoon1)*

did you pressure test the intake system? if so then you might have used too much pressure and moved a turbo oil seal... Ive seen it happen before...


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## bluelagoon1 (Apr 21, 2005)

*Re: (2035cc16v)*


_Quote, originally posted by *2035cc16v* »_did you pressure test the intake system? if so then you might have used too much pressure and moved a turbo oil seal... Ive seen it happen before...

would that send liquid oil is large quantities to the pcv system?


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## GLS-S4 (Jun 6, 2005)

*Re: (bluelagoon1)*

OP: As already mentioned, suspect Oil Pressure Sensor. Also may want to consider something like Seafoaming the engine.
bluelagoon1
How much pressure did you use to test intake?
Were you dripping oil out both DP flex joints?
I've heard of ppl going as high as 25psi but personally I use 10psi for basic tests and the rare and quick peak up to 15-18psi to test for my chip peak boost pressure.
Also suggested is to keep intake pressure test time to a minimum, meaning don't leave intake pressurized any longer than it needs to be in order to complete the test.
The only time a functional PCV system dumps vaporized oil mist into the intake is when in boost and it collects in the intake low spots.
Suggest pull lower intercooler hoses to check for excess large quantities of oil. There should be some as in half a cup or so, but not the puddle forming volumes you describe.
Might be worth replacing PCV to test your theory.


_Modified by GLS-S4 at 10:56 AM 7-31-2008_


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