tprjim

My '02 S has started to make a popping noise(and revs to 1000 rpm only) from the airbox and now makes a shrill noise on start up. Sounds like a heat shield but could it be timing chain related? It doesn't happen at every start.

Starter986

I'm thinking chain tensioner(s). They'll rattle at cold start up and, usually... after car is warm... will stop making the noise when starting... until the next cold start.

The airbox... popping... I've no idea, sorry.

tprjim

Didn't want to hear that! Only 40K on the car. Thanks

pilot4fn

If the 'shrill' noice is only immediately after the engine fires up, it most likely starter. Cure is a new started or opening, cleaning and lubing the old one.
Starter noice I refer to is on this video right after 0:55 spot:

This one is a good video on how to fix the old sarter if the issue is the stater:

Starter986

I forgot about that noise. Twice I pulled my starter... lubing it... hoping the sound would go away, annoying ore than anything. My continued reading led me to believe, strongly, that what I thought was the starter sound was... is... in fact, the chain tensioners.

That said... OP... I'd follow the recommendation of Pilot and pull the starter... lube it... go back to town. Good luck.

enorab

Did you do anything with your chain tensioner issue?

John

Starter986

Yes. I continue to ignore it. However, I do inspect my oil filter at changes and... every couple years, drop the oil pan to look for brown, green, black anythings that don't look like oil, .

Every morning I start the car... and the chains rattle, I visualize the chains running on that plastic with little specks falling off. Then I go about my day, lol.

One day I'll hook it to a Durametric to see what are the deviations. I'm not dropping any money into repairing those things. Yet.

enorab

Thanks for that input. I believe that I have the same problem. After car sits for a few days, upon startup I hear the noise. Successive startups within a short period, the noise is not there. I assume that the oil drains out of the tensioner much like a hydraulic lifter, hence the noise until the oil builds up in the device. I found someone with the Durametric and will have him hook it up and make sure there is nothing that needs attention at this time.

John

Gasngo

I would not ignore it! The bottom tensioner has been updated 3 times if I'm correct. That chain slaps those plastic guides and breaks things loose also the slack tugs on the IMS. Food for thought! A dry bearing or worn bearing on a starter could have a wind down noise after engagement which would be a shrill noise and chain would be a quick ratatat tat slapping sound. It would be ideal to have someone start the car and you stand out back for a better ear.

Starter986

There you go... yes... more a ratatat sound. The shrill sound could be described as the starter slowly retracting that thigamajig.

It's actually more of a "**** it" than actual ignoring. I know the sound exists. I know the sound is'nt for a good reason. I know that short of having it repaired ($$$) it won't get any better. Then the ****-its set in.

Gasngo

If the lower tensioner has not been replaced on your car they are cheap enough and easy to access. The updated version looks different the the original. In my latest reading it seems thats a hot ticket item if you will and some believe it plays heavy on the IMS also.

tprjim

THANK YOU!!! Starter motor it is!

Gasngo

Yep I have heard many a starter motor buzz because lack of lube. It would be worth investigation if the tensioner is the most current version. If not get it taken care of.