Noise Coming From Timing Belt Cover, Rear Sprocket

[Chaz9496]

On my 3.0 engine I just had put in a few months ago, I'm getting a knock/rattle from the rear of the camshaft sprocket cover area. It starts about 2 min or so after cold overnight start-up, then quiets down after a few minutes. When I push down on the cover above the sprocket, it stops. It's a "plastic sound" knock/rattle from the cover. I did have the belt replaced as well. This just started last week and doesn't do it the rest of the day, even after sitting for a few hours when it's cold out. I've never heard anything like that before. I'm hoping I can still drive it safely without any damage to the belt. Any ideas ? I was going to have my mechanic check it next week. I didn't know if i should park it until then or not. Thanks for any suggestions.

[lrbraner]

I would park it until you know what the problem is. Not worth taking the chance.

[Chaz9496]

I called my mechanic today and he said the same thing. I wouldn't think its too serious because it doesn't last that long, but you never know. If it did it all the time it'd be easier to diagnose.

[Rj 2000 LS2]

Remove timing belt cover and inspect the timing belt components.

[Chaz9496]

I read something today on a Saturn mechanic website that a Saturn owner back in 2018 had the simular noise on his L300. Turned out it was the timing belt tensioner. If that's the case, it could be catastrophic if the belt would come off. The problem is that I have no loaner vehicle. I can't afford to rent anything over the weekend until I can take it in next week. I'm kinda in a hard place with what to do.

[Rj 2000 LS2]

It may run for another 5,000 miles or quit in less than 10 miles. When our timing belt tensioner failed, we had just driven 200 miles, I noticed a lack of power going down the highway. It was intermittent. A few days later after not driving it, I took my wife to work and at a stop light, the engine started jumping around and ran like crap with engine light ON. I managed to drive it to a repair shop. They inspected the timing belt and found the belt jumped a tooth on cam1. Their repair cost was too high and I managed to drive it to resting place where I could work on it much later. The belt tensioner was expired. I installed a timing belt kit and it's been running strong ever since.

Risk: Interference Engine i.e. if the timing goes out of time, for whatever reason, you run the risk of damaging valves. I got lucky, but most don't.

If you have to drive the vehicle... plan for it to die. Carry jackets/clothes, water and everything you need to stay warm in case it quits on you. Hell, put a bike on the trunk for alternate transportation.

Chances are, it will run for some time yet. But, don't drag race!