Oil leak that's not valve covers?
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From: Scotia, NY
Oil leak that's not valve covers?
1993 90cs Quattro, AAH V6.
I'm having some difficulty locating an oil leak that's coming from the passenger side front of the engine somewhere.
This past week I replaced my valve cover gaskets and an oil pressure sender and then degreased everything a couple of times.
I have a leak, that as far as I can see, is dripping from the front lower lobe of the exhaust manifold onto the top/back of the alternator.
Problem is, I can't see/pinpoint exactly where it's coming from.
It's definitely not the valve cover as I've verified there is nothing seeping from there now. What else could it be in that location?
It's really not easy to see what's up there because of the exhaust shield and the timing belt cover. I've been under the car with a light and on top with a mirror and am not having any luck.
Any ideas?
I'm having some difficulty locating an oil leak that's coming from the passenger side front of the engine somewhere.
This past week I replaced my valve cover gaskets and an oil pressure sender and then degreased everything a couple of times.
I have a leak, that as far as I can see, is dripping from the front lower lobe of the exhaust manifold onto the top/back of the alternator.
Problem is, I can't see/pinpoint exactly where it's coming from.
It's definitely not the valve cover as I've verified there is nothing seeping from there now. What else could it be in that location?
It's really not easy to see what's up there because of the exhaust shield and the timing belt cover. I've been under the car with a light and on top with a mirror and am not having any luck.
Any ideas?
Last edited by GuyllFyre; Aug 15, 2011 at 04:08 AM.
Thread Starter
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From: Scotia, NY
I should also note that I've had a persistent warning beep in the car and now that I've replaced the oil sender, have a dimly lit oil light in the cluster when I'm at idle.
This is something else I've been working on tracking down and will be installing a pressure gauge to see what's going on but it may be related.
Theoretically, before I got the car, they did head gaskets, valve cover gaskets, oil pan gaskets, and heater core.
This is something else I've been working on tracking down and will be installing a pressure gauge to see what's going on but it may be related.
Theoretically, before I got the car, they did head gaskets, valve cover gaskets, oil pan gaskets, and heater core.
AudiWorld Senior Member
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From: Cincinnati OH
I had a leak in the valley pan under the IM between the two valve covers. it was pooling there and running down the sides of the block.
There is a ton of info on this forum on the valley pan leak --
Also, while you are there, the oil check valves inside the valley pan may be the source of your oil light. There are two valves in the valley pan and one in each head. IIRC the failure of these valves can cause low oil pressure at idle.
There is a ton of info on this forum on the valley pan leak --
Also, while you are there, the oil check valves inside the valley pan may be the source of your oil light. There are two valves in the valley pan and one in each head. IIRC the failure of these valves can cause low oil pressure at idle.
Thread Starter
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From: Scotia, NY
Yikes! $55+ each? and I need 2? Plus intake gaskets, EGR gasket, and valley pan gasket?
078 103 175 D is the part number I've come up with.
Any source for these at a reasonable price?
Looks like I should also do the ones in the heads.
078 103 363 P is the part number.
$45 each so far in searches. Another post had mentioned getting these for $18 somewhere...
Will also probably have to get two new valve cover gaskets as I sealed mine down really well...
078 103 175 D is the part number I've come up with.
Any source for these at a reasonable price?
Looks like I should also do the ones in the heads.
078 103 363 P is the part number.
$45 each so far in searches. Another post had mentioned getting these for $18 somewhere...
Will also probably have to get two new valve cover gaskets as I sealed mine down really well...
Last edited by GuyllFyre; Aug 15, 2011 at 07:15 AM.
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From: Canada
Re: Drain-back valves inspection, etc....
It may be that these valves are dirty, but otherwise fine. I've only looked at those in the valley, cleaned them and put them back. Perhaps the others can be treated similarly?
Just a note to ensure you find the valley pan truing procedure (which you may have already found!). It's not just that a new VP gasket is required.
The alternator fan moves some air, so it may be necessary to clean it up and then watch the leak develop from scratch, while the car is stationary.
My oil pressure sender passage was clogged; the clearing of which extinguished my light.
Just a note to ensure you find the valley pan truing procedure (which you may have already found!). It's not just that a new VP gasket is required.
The alternator fan moves some air, so it may be necessary to clean it up and then watch the leak develop from scratch, while the car is stationary.
My oil pressure sender passage was clogged; the clearing of which extinguished my light.
Thread Starter
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From: Scotia, NY
I'd love it if I knew a cleaning would fix them but I'd rather not have to do the job twice, if at all possible.
Saw the issue of the valley pan being warped and needing a quick sanding/flattening. Thanks for mentioning it though.
I've cleaned the oil up twice, I'll have to get a better peek under the intake manifold, I thought I saw oil under there but it's so hard to see. Valley pan makes sense since I also thought I saw fresh oil running down the back of the motor also after two degreasings.
Oil flows freely from the sensor passages when the sensors are pulled, so I think that the passage is clean. I've had both out plus the fitting with the banjo bolt through it that mounts both sensors.
I also have an issue with the EGR. Keeps throwing a code with "Implausible Signal." Wish I could find the definitive FAQ that tells me how to recode my ECU to eliminate the EGR.
Saw the issue of the valley pan being warped and needing a quick sanding/flattening. Thanks for mentioning it though.
I've cleaned the oil up twice, I'll have to get a better peek under the intake manifold, I thought I saw oil under there but it's so hard to see. Valley pan makes sense since I also thought I saw fresh oil running down the back of the motor also after two degreasings.
Oil flows freely from the sensor passages when the sensors are pulled, so I think that the passage is clean. I've had both out plus the fitting with the banjo bolt through it that mounts both sensors.
I also have an issue with the EGR. Keeps throwing a code with "Implausible Signal." Wish I could find the definitive FAQ that tells me how to recode my ECU to eliminate the EGR.
Last edited by GuyllFyre; Aug 15, 2011 at 11:08 AM.
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I believe the EGR implausibility is the best indicator of your valley pan leak. That's the logical place for oil to stick (and in your case, get dirty) when seeping from the valley pan upon ACCELERATION.
Upon DECELERATION, it seems logical that you would then have a seepage down the driver's side front of your block.
Of course, this would be entirely dependent upon an oil seal gap being big enough that it would adversely affect pressure and trigger... wait for it...
...an oil pressure warning light at idle.
Am I positive that's everything that's currently going on? Hell no. But damn guys, it's got webbed feet and a bill. It's quacking, and it has no fur. I'm certainly NOT going to point my finger and shout "Platypus" here, ya know what I mean?.
Upon DECELERATION, it seems logical that you would then have a seepage down the driver's side front of your block.
Of course, this would be entirely dependent upon an oil seal gap being big enough that it would adversely affect pressure and trigger... wait for it...
...an oil pressure warning light at idle.
Am I positive that's everything that's currently going on? Hell no. But damn guys, it's got webbed feet and a bill. It's quacking, and it has no fur. I'm certainly NOT going to point my finger and shout "Platypus" here, ya know what I mean?.
Last edited by Loudgoldwing; Aug 15, 2011 at 11:00 AM.
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Thread Starter
AudiWorld Member
Joined: Nov 2010
Posts: 247
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From: Scotia, NY
I might try to go cheap here, EGR, intake, and valley pan gaskets, clean the hell out of everything, and see what happens?
Thanks for the help guys, I appreciate being pointed in the right direction. Now to order the gaskets and tear into it...
Thanks for the help guys, I appreciate being pointed in the right direction. Now to order the gaskets and tear into it...
AudiWorld Senior Member
Joined: Sep 2010
Posts: 623
Likes: 5
From: Cincinnati OH
Do you have valve train noise at idle?
The last thing you'll want to do is fix the valley pan and have to tear into it again. It's a finicky gasket that I had to try twice to get right. I hope to never get in there again.
I have the valves I took out of mine if you want them (which I think are probably good - I replaced them while fixing the leaky gasket). That way, if you get in there and find you have a bad valve, you can put something in that presumably isn't bad right away rather than waiting for a mail order.
If it were me, I'd get new valley pan valves. The valves in the heads are another story. The valve covers can come off and go back on a lot easier. I'd start with the others.
The valley pan valves from Bentley...
and the pressure relief valves (#7)
The last thing you'll want to do is fix the valley pan and have to tear into it again. It's a finicky gasket that I had to try twice to get right. I hope to never get in there again.
I have the valves I took out of mine if you want them (which I think are probably good - I replaced them while fixing the leaky gasket). That way, if you get in there and find you have a bad valve, you can put something in that presumably isn't bad right away rather than waiting for a mail order.
If it were me, I'd get new valley pan valves. The valves in the heads are another story. The valve covers can come off and go back on a lot easier. I'd start with the others.
The valley pan valves from Bentley...
and the pressure relief valves (#7)