Hello from Great Britain! This being my first post on this forum. I've gone through many pages on here and found that this problem is not unique but hope that someone may be able to help.

Having owned a plethora of Audi's over the years, I now have a '94 100E Quattro 5 speed with climate control. It's in excellent original condition having only had two owners.

Soon after purchase in September, I had the cam-belt replaced as it was overdue along with oil and filters. Since then I've had lifter noise which occurs soon after start up but after a couple of quick revs it clears and can stay quiet for several minutes. As soon as the oil & water get a bit of temperature into them, it starts ticking and will remain doing so. However, this is only on idle! Bring the revs up a couple of hundred and it goes.

In no particular order, I or my mechanic have done the following:

4 different grades of oil: 5w30, 5w40, 10w40, 15w40
Mahle and now a VAG oil filter
Oil pan off to check pick-up pipe etc.
Valley pan check valves (replaced, but old ones seem fine)
Cylinder head pressure relief valves
New lifters

One odd thing to note is that the flow from the cylinder head pressure relief valve can be seen if the filler cap is removed even though it is hidden by the baffle plate. Bring the revs up a touch and the flow is significant. However, it can be flowing like this on idle too (indicating that there is too much pressure in the gallery) but the lifters are ticking!!

It seems odd that this engine can purr like a kitten a minute after starting from cold, yet within a short drive can sound like an old diesel!

Oil pressure on the gauge (yeah, I know the sensor's at the bottom of the engine) shows 4+ bar cold and never less than 2 bar hot even after a good thrashing.

Any help/ advice welcome!

Alan

(P.S: my other ride is a '95 Mustang SVT Cobra. Maybe only four of these in the UK)

http://www.flickr.com/photos/acd40/9672933686/http://www.flickr.com/photos/acd40/9672933686/, on Flickr

 

when i had the heads off my last 12v car that had awful lifter tick. I noticed the lifters had very small holes leading to each one, some of them had become blocked up with junk, I rodded the holes out and cleaned it all thoroughly and replaced the lifters and it was a very quiet car.

 

we have a product called sea foam http://shop.advanceautoparts.com/web...ontent=6410004

i highly recommend it, dump about a 1/3 of a can in to your oil, and drive with it for about 200 miles, do an oil change.
btw, you have an extremely good looking car, except your steering wheel is on the wrong side :-P

 

Thanks for the replies. I don't think any crud in the oilways or glazing in the lifters is the issue. The engine has been flushed with a very good and effective flush and when the oil pan was removed it was totally clean.

The lifters are new anyway so the problem cannot be there.

Alan

 

Ran the motor for a bit today until the ticking noise started. Took the valve cover bolts out and gently lifted the cover back until I could see the pressure relief valve. So, with the noise present, the valve was leaking off suggesting that there is sufficient pressure in the head oil gallery. These valves are new.

This answers one question but raises another!!

Alan

 

Have you double checked the timing belt? Maybe the belt is off one tooth on one or both camshafts? You have checked everything I can think to check on the lifters and oil system but seeing as it started right after the timing belt change I would check it. It may be igniting the fuel after the exhaust valves have opened and are slamming them up and collapsing the lifters and making the noise. I know its a lot of work digging in to the belt, but its the only other thing that I can think of.

Good Luck

 

Yes, I wondered if the belt change has anything to do with this. There wasn't any problem before except maybe a little when cold.

But if the belt was one tooth out, and it would need to be on both cams as the noise is on both sides, surely that would cause noises at all times unless the ECU is trying to correct it.

Also, the ticking, tapping or whatever noise does seem to be temperature/ pressure related. I can start the car, give it a couple of quick revs to 'clear' the noise and leave it at idle. It will be perfectly quiet for maybe five minutes and as soon as pressure drops to about 3.7 bar the noise starts and can be quite loud. It will only get quiet again (but not totally) until 2 bar. I'm currently using 5w30 oil.

Alan

 

Maxlife will quiet lifters. Sodium based additive pack, same as Mobil Clean, but I have seen the Maxlife work with mine own eyes.