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Discussion Starter · #1 · (Edited)
It sounds like a crackling / pinging sound. Happens on initial acceleration through gears. I think it may be the timing chain giving me a sign that it is going?

My NA has the same sound and has for years, but it is MUCH more noticeable in that car. It is hard to hear in my SE because of the loud exhaust but the best way I can describe it is a crackling sound...

Any insight would be appreciated.

EDIT - happens around 2k rpm, whether in gear or in neutral. Can be decelerating or accelerating.
 

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I want to doubt its the turbo. That thing was so tight when I took it apart, and unless it is smoking like crazy its pretty doubtful.

A grinding noise eh? Can you hear which side its coming from? Can you hear it when the hood is popped? Could be something vibrating. I don't know if the timing chain was ever replaced, but I doubt it was. It could be a timing chain guide.
 

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Discussion Starter · #4 ·
I want to doubt its the turbo. That thing was so tight when I took it apart, and unless it is smoking like crazy its pretty doubtful.

A grinding noise eh? Can you hear which side its coming from? Can you hear it when the hood is popped? Could be something vibrating. I don't know if the timing chain was ever replaced, but I doubt it was. It could be a timing chain guide.
Its getting worse too, didn't do it at all this morning, now its bad bad. I don't wanna believe it was the turbo because it boosts like a champ still, but if you have the hood popped you can hear it coming from around the turbo, or down there somewhere. So it is either down by the turbo or yes right on the timing chain side. stay under 1500 rpms you dont really hear it, but it is getting much louder the more I drive it.

How would I go about checking the timing chain + guides. I have zero experience regarding timing chains.
 

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there is a timing chain adjustment you can check. It has a spring the provides tension on the chain as it gets older and stretches. It is located behind the engine right by the timing cover under where the PCV nipples comes out of the timing cover
 

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Discussion Starter · #6 ·
there is a timing chain adjustment you can check. It has a spring the provides tension on the chain as it gets older and stretches. It is located behind the engine right by the timing cover under where the PCV nipples comes out of the timing cover
Alright I will check that tomorrow along with a few other things. So what is it I should be looking for when I check the adjustment? Is there a way to actually "adjust" the chain that may solve the noise? I am kind of in the dark about timing chains.
 

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Discussion Starter · #8 ·
Problem found (hopefully) and half solved (hopefully)

Both idler pulleys were bad, the rear one being very bad, while the middle one above the crank was just 'not good'. Also my water pump was shot, the pulley moved side to side big time, which must have been my noise. I ran the engine with the serp. off, revved the engine to the 1900rpm trouble spot, and there was no noise.

Got a new rear idler pulley, couldn't get a center one though, but thats okay as it is in ok condition. Also had a spare water pump laying around, o rings seem to be good too... as it is 'dealer only' part, or eeuro part.
 

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You, don't actually need that center idler. the later ng900's and the og9-3s do not have that center idler.
 

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Discussion Starter · #10 ·
You, don't actually need that center idler. the later ng900's and the og9-3s do not have that center idler.
Yeah my 97 NG bypasses that. I dont have a short belt lying around though, so I need the idler for now.

Will bypass the idler when I bypass my AC
 

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Yeah my 97 NG bypasses that. I dont have a short belt lying around though, so I need the idler for now.

Will bypass the idler when I bypass my AC
Cool.

Just wanted to make sure you were aware of that so you don't waste any money on something that is unneeded.
 

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Discussion Starter · #12 ·
Cool.

Just wanted to make sure you were aware of that so you don't waste any money on something that is unneeded.
I appreciate that. They want 40 bucks for the pulley at advanced and 57 at auto zone.

Hopefully when I get all this in it will be as good as new, or at least back to the way it was ha.
 

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Discussion Starter · #13 ·
New grooved pulley, new/used water pump, everything reattached (turbo intake hose is a bitch to put on wow), filled coolant to cold, ran for 20 mins or so till the fan came on, turned it off, and all seems well. Will top off the coolant tomorrow morning and give it a go.
 
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