3.0L M3 Valve Noise

[tooli21]

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My car has developed a ticking noise in the last several days. The noise is at a constant interval while idleing. I can't hear the tick when I rev the engine, but when the rpms drop back down, just prioir to reching idle level, I seem to hear the noise increase slightly in frequency, then back to the normal rate. There does not seem to be any loss in power, and the idle is still smooth. I pulled the exhaust manuifold and head shrouds, and the noise appears to be coming from the exhaust side of the engine,, near the furthest cylinder back.

I'm thinking this is a common valve knock, and nothing deep inside of the engine. Does anyone have any other diagnosis? Has anyone had to get a valve job recently, and how much did it cost? I currently have M1 10W-40 in the car, and was thinking of trying a slightly thicker oil. Has anyone used a gas additivre (something to clean the valve train), or are these not recommended in BMWs?

[BadGTho]

have you ever had the valve retainers replaced? does the noise go at the a 1:1 ratio with RPM?

[slickfast]

It's not coming from your VANOS unit is it? Your plugs are all tight as well, right? Just trying to rule stuff out, otherwise I'm with Ben: it's the valve retainers.

[BadGTho]

i never said it was valve retainers/// i just asked if they were done...because they should be.

it's probably a lifter.

[tooli21]

The noise is a 1:1 ratio while at idle. The noise is coming from the back of the engine, so I don't think it is VANOS related. I recently replaced an o-ring on the VANOS unit while swapping my valve cover gasket.

I got the car in november, and my records, which appear fairly comprehensive, don't show any valve retainer swap. What is a valve retainer, and is it an expensive fix, or a DIY? To my knowledge, the car has hydraulic lifters, which sounds like an expensive fix. Are these typically replaced, or is there a common rehab for them.

I will check to make sure all plugs are tight tomorrow, and will post an update.

[BadGTho]

Originally Posted by tooli21

The noise is a 1:1 ratio while at idle. The noise is coming from the back of the engine, so I don't think it is VANOS related. I recently replaced an o-ring on the VANOS unit while swapping my valve cover gasket.

I got the car in november, and my records, which appear fairly comprehensive, don't show any valve retainer swap. What is a valve retainer, and is it an expensive fix, or a DIY? To my knowledge, the car has hydraulic lifters, which sounds like an expensive fix. Are these typically replaced, or is there a common rehab for them.

I will check to make sure all plugs are tight tomorrow, and will post an update.

a 1:1 ratio with RPM is typically a lifter.. but could be an exhaust leak.. i know that sounds dumb but they can sound alike. there are some easy checks.

valve retainers are little rings that hold the valve into the head.. and prevent it from dropping into the cylinder. all pre - 10/95 M3s had an issue with these that can cause them to fail. if they do fail, so too does your motor.

the repair most often requires removal of the head, though some use compressed air to keep the valves in while the retainers are out.

this is not a DIY... and i will await colin's response as to how this part can make noise as it does not move.
The car does have hydraulic lifters.. all US spec E36 M3s do. they have engine oil run through them to keep the lifter tip "pumped up" and not "collapse" causing a limited range of valve function.

when one fails it needs to be replaced. the labor is costly, the part is not.

what oil do you run? how full is it? sometimes you get lucky and running a thicker oil and overfilling by .5 qts can fix this.

[tooli21]

I am using M1 High Mileage 10W-40. I head about the overfill trick and topped it off to about 1/4 quart above the line, so I will try adding a little more. If the lifter does need to be replaced, what is a good $ range I will be looking at. A couple months ago I had a mis-diagnosis for replacing the head gasket, also expensive labor-cheap part job, and estimates were $2500-3000. Obviously, I hope its not that much.

One more thing, I was at the auto store yesterday, and saw a valve system cleaner that said it quiets lifter noise. Do you guys think this is worth a shot, or has anyone had issues with oil additives in the past? Also, does seafoam claim to address valvetrain problems? I have head great and horrible things about seafoam.

[BadGTho]

i would not rely on an additive to fix this.

run delvac 15w40... overfill slightly.

if it still ticks, it's done.

[tooli21]

Here's an update to bring closure to this thread...

I turned out to be a loose spark plug. I tightened all the plugs and the noise is gone.
Make sure to rule out all possibilities that you can check yourself before taking it to the shop