Resolved 1G Need help diagnosing this Popping/Knocking sound

[1991dsm59]

After sitting for a week or so started up and started hearing this noise coming from timing belt side of the engine. I know there is some lifter tick in the video that is not the sound I’m referring to. The sound I’m referring to is the scraping/bubbling/puffing sounds(hard to explain the noise)

Planning on doing a compression check. Also adding a video with the upside down oil cap for blow by. Not ruled out an exhaust leak either. Can’t really hear the sound higher in the revs but not convinced it goes away when higher in revs but when it comes back down to idle you can hear it again. Let the car warm up to operating temp and it was still there as well.

Mostly wondering if anyone has encountered this before and solved the issue.

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[99dsmer4g63]

Can’t tell you what is is.

I would start taking accessory belts off one at a time. If you end up with no accessory belts and the noise is still present I would remove the lower timing cover and investigate further.

Good luck, Daniel

 

[1991dsm59]

Can’t tell you what is is.

I would start taking accessory belts off one at a time. If you end up with no accessory belts and the noise is still present I would remove the lower timing cover and investigate further.

Good luck, Daniel

Good idea didn’t think about trying this will try when I have the time

 

[DSMPT]

Also I would remove the timing cover and the cam gear cover to make sure nothing is coming loose and scrubbing inside the cover.

 

[99dsmer4g63]

Very well could be the water pump pulley scrubbing the lower timing cover.

-Daniel

 

[evil_eagletalon]

Sounds like hydraulic timing belt tensioner. Remove the timing cover and inspect the hydraulic tensioner you should NOT be able to move the tensioner by hand it takes a vise to collapse it. If it is bad please dont use an aftermarket one or you will find yourself doing it again within a year.

 

[TerminalTalon]

Pull the upper cover to check for tension.

 

[1991dsm59]

found what was making the sound. The balance shaft belt started losing teeth and the sound was the belt slipping on the pulleys where it was lacking teeth. Got very lucky the cam belt didn’t slip a tooth

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Had taken all accessory belts off and noise was still present. Started taking the timing belt cover off when bits of belt started falling out.

Now I need to figure out if it’s safe to leave the balance shaft in without the belt or do I need to pull it so I never have to worry about it again

 

[curt-s]

You have two shafts. If you take the belt off the front, the rear will still spin with the oil pump so you're adding imbalance. The more common half-removal is going to a stubby shaft in the rear but keeping the front in as an alternative to rotating the bearings to block off the oil holes.

 

[1991dsm59]

Is it possible to do the half delete with the engine in the car?

You have two shafts. If you take the belt off the front, the rear will still spin with the oil pump so you're adding imbalance. The more common half-removal is going to a stubby shaft in the rear but keeping the front in as an alternative to rotating the bearings to block off the oil holes

 

[curt-s]

Is it possible to do the half delete with the engine in the car?

It is, it does require you to remove everything necessary to get at the front case and also remove it.
You'll likely have to allow the engine to drop on that side so that you can pull the shaft all the way out, clearing whatever suspension/steering components that are in the way.

I've never done it that way but @97egl lays out a method here: https://www.dsmtuners.com/threads/balance-shaft-delete.545785/post-153906241