SpronglFan

Okay I know there's a ton of previous post but this is more of a source question. Scenerio = It's a 93 90CSQ 6cyl 12v, When I bought this car it had about 90k kms on it and there was a lot of ticking from the valves. It was noisy all the time, at idle and higher rpm and across the temp range. I switched to 20w50 Amsoil synthetic, ran a little smoother but the noise remained. If I change the lifters, what caused the noisy lifters, won't it just work the same on the new ones?

MikTip

<center><img src="http://www.tpub.com/engine3/en3_files/image084.jpg"></center><p>Hydraulic valve lifters (lash adjusters) are used on some engines to reduce noise, &amp; avoid the necessity of a clearance otherwise needed in the valve gear to allow for expansion resulting from temperature changes. Hydraulic valve lifters also eliminate the need for manual adjustments(shims) to take care of the wear at various points of the valve gear. They may be installed on the rocker arms, valve bridge, or cam follower.

Hydraulic lash adjusters may vary in design but generally consist of such basic parts as a cylinder, a piston or plunger, a ball check valve, and a spring. As precision parts, hydraulic valve lifters or adjusters require special care in handling and must be kept exceptionally clean. Abrasive materials must not be allowed to enter a hydraulic lash adjuster if the lash adjuster is to perform its function satisfactorily.

Hydraulic lash adjusters will make noise(tapping) when worn, because they no longer trap oil internally. Thus their cushioning effect &amp; self-adjusting clearance is gone, reducing valve-train performance.

Replacing worn lifters, often restores lost engine performance, because the lifters are pumped up to their max, by oil pressure, and they will open the valves to their maximum! Worn lifters do not open the valves all the way. )

thermonuclear

How much lift do you think the lifters lose after, say... 200k miles? Very much?

MikTip

Seems some folks drive their Audi's 200K+ miles, and never experience the lifter noise!

Others, like myself, seem to get the lifter noise
all too often.

There's much speculation as to lifter noise cause &amp; cures.

Mine make noise I change them. Others like to experiment with different oils, &amp; additives.

amiro

I'm actually an A4 owner, but your post i bumped into seems to describe my problem too! I've got a 2000 1.8T engine, with only 15,000 miles, and occasionally, when at idle, i hear this loud ticking sound, at the same frequency as when you open the hood, and hear the engine. I took it in, and of course, since they couldn't hear it at that time, they didn't do anything. Someone said it could be lifters.

I was curious, could i have something seriously wrong (and i should push them to look again even though it's not there all the time), or is it probably not a big deal?

Thanks!

squrlathon

If you've seen some of my posts over the last couple of months then you'll know what I've been going through with the ticking in my engine. What was originally diagnosed as a routine worn lifter problem turned out to be something entirely different.

In other words, the lifters were replaced but the noise was still there. So they replaced the lifters again and the noise was still there -- so the problem is elsewhere. Now the interesting thing is that I listened to Greendoh's 90 the other day (he is also a forum member) and his car sounds the same as mine (I'm referring to the ticking noise in particular, other than that the engines are relatively quiet), although his engine has 200,000 kms on it, but his mom's car is sooooo quiet, so smooth sounding, like a car fresh off the showroom floor, I kid you not!. So I figure that if his car is noise with old lifters and mine is noise with new lifters then the problem is that there isn't enough oil pressure in the head so the problem is with one of the valves in the oil circulation system, or it's the oil pump itself. This is what is being addressed with my car as we speak.

This problem was suggested to me ages at by MikTip and others, it's also on the 12v.org website etc. My mechanic didn't act on it since he checked the oil pressure, thus ruling out that the oil pump was bad -- but that doesn't mean that the pressure at the top of the engine is right. You can check the pressure in the heads themselves, so I would suggest to do that before you do anything else.

To make a long post even longer....since I have seen that most of the 12-valve engines sound like that could benefit from checking the oil pressure in the head and not just replacing the lifters. Low oil pressure in the head could lead to premature lifter wear etc. etc. etc. We'll see what results I get in a few days when the oil-non return valves and pressure-relief valves come in for my car.

Mancubus

My car makes that same ticking sound. Let me know if you resolve the problem (I'm also in T.O)

M2thaJ

Maybe a bend pushrod try a compression test 🤷🏽‍♂️