Davebrossi

I completed an IMS replacement three weeks ago along with an AOS replacement, and I've been putting miles on my car to ensure everything's gone back together. Thus far everything's been great, and I've been thrilled. However, this afternoon when getting ready to garage my Boxster S, I heard a ticking noise at idle. I'm running Brad Penn oil, and I've put 300 miles on the car since I completed the rebuild. Is this a stuck lifter? Does that spell doom and gloom? I've attached a link to video I shot of the noise. I saw the earlier thread about a similar situation, but at 68,XXX miles, I wanted to be sure it wasn't something different. Thanks all!

Macster

The noise has a bright metallic sound to it which is characsteristic of a problem in the valve train area.

But you or someone needs to as close as possible pinpoint where the noise is coming from. Where it is coming from helps to better guess the underlying cause.

Having the car in the air and with a stethoscope at hand is called for.

Until you (we) know where the noise is coming from it is all guess work. It is guess work afterwards until say the suspected bank's camshaft cover is removed and the noisy lifter (if that is what if proves to be) is found and replaced.

I'm a bit worried about the IMS. Oftentimes when a noise appears out of the blue it is related to something just done. Last thing touched first thing suspected.

So I would caution you about unnecessarily running the engine and listening to the noise over and over again. Everything you do should be aimed at determining where the noise is coming from and focusing on that area.

Skootnasty

If that is truely at idle, it sounds much too fast for a single lifter to me. A stethoscope, or chassis ear system needs to be used to pinpoint a closer proximity to the noise.

Chains/guides and rods are typical suspects of fast metal knock/ticks/rattles from inside an engine.

Why did you replace the bearing? Was there any metal intrusion into the oiling system?

Do you have access to Cam deviation PIDS in a scanner? That could determine the likelyhood of chain failing, if one side was farther out than the other. If the new bearing was damaged during install and is allowing the sprocket/chains to move/rattle (yikes), then you will want to run it the absolute least amount possible to verify this.

It may be worth just removing the trans again and doing a visual inspection, probably even pulling the flange back out.

Skoot

Davebrossi

Cam deviation has remained the same as prior to IMS install at -6 and -1 respectively using the durametric software. I changed the IMS bearing solely as a precautionary measure. I heard the sound once prior to the IMS install and have not heard it since the video, but I'll continue to monitor the cam deviation.

earossi

Assuming that the engine is idling at 800 rpm, and knowing that the cams run at half engine speed, translates into each cam running at 400 rpm. At that speed, a collapsed lifter should be heard at a frequency of about 6 to 7 "clicks" per second. When I listen to the sound clip of the engine, the noise seems to be in or close to that range. So, I think that the noise could very well be associated with one of the cams, and more than likely a collapsed lifter.

I agree with Macster's comment that when something strange appears, you should look at what was just done to the engine.......which in this case, was replacement of the IMS bearing. So, in parallel with looking for a bad lifter, Dave should be re-tracing all of his steps to make certain that there is not a loose fastener that is vibrating at some harmonic induced by the engine.

Since the cars cam deviations are unchanged from before install of the IMS bearing, and since they seem steady, I question whether he has a failed IMS bearing.

Lastly, Dave decided to replace the IMS bearing for insurance. What took the car down was failure of the AOS. So, the question is posed of what (if any) damage was done to the motor due to the failure of this item. The car began smoking profusely, and was rapidly shut down and towed home. So, the question is if the failed AOS could have contributed to the noise currently being investigated.

Audi Junkie

Marvel Mystery Oil did wonders for my valvetrain. Just add it 500-1000 miles before oil change. Remember the large oil capacity means 2X the normal amount.

Brad Penn is an amazing oil.


fwiw, my last engine noises were from the pulleys. Replaced them and it's smooth like butter.

Macster

I have to stress knowing as precisely as possible where the noise is coming from is important to better identify the cause.

It might be a "stuck lifter" but it might be chain tensioner or it could be something else. But it should be fairly easy to pinpoint where the noise is coming from and from knowing this making an educated guess as to what is the cause is more likely to be right.

About the only thing I know a failed AOS can do is if left alone too long is it can result in a hydraulic lock up of the engine.

When I called about bringing my car in the SM advised me to not drive the car. He told me about another Boxster owner who's car was manifesting the same symptoms as my car who insisted on driving the car and the engine suffered from a catastrophic lock up.

The above then makes what happened to me a bit upsetting.

When I went to collect my car the SM informed me the engine had experienced a very mild lock up as the tech was performing a compression test of the engine. I was aghast this test was done *before* the AOS was replaced. As per the SM's advice I had the car flat bedded to the dealer at the cost of around $150 (40+ miles tow). Then to have the tech do to the engine what I paid this money to avoid upset me no end.

Fortunately the lock up appeared to have harmed the engine not one iota as this occurred over 180K miles and 2 AOSs ago.

The source of the noise, the size of the area from which it is coming from, needs to be determined as best it can be.

RaceClag

It appears to be a similar sound to this... Apparently in teh comments it states: "The noise is fixed. It was a ex. lifter on piston #3. I changed the oil to 0-40, and after running for 10 mins the noise went away. I did end up changing the IMS bearing, but that wasn't the cause."

Hope this helps.

Davebrossi

It does, thank you very much! In my case the weight oil I'd put in was far too heavy. A little Marvel Mystery Oil, correct weight oil and all's well. Been keeping Derivation logs on both cam banks, they vary, but by less than one tenth of a degree.