strange noise from engine?

[Milo]

I have a noise that sounds a bit like a rattly sewing machine. it sounds like it comes from the front side of the engine on the firewall side. could it be the cam chain on that side? has anyone experienced a sound similiar? Thanks in advance. I am going to try a stethoscope today and I will post my findings.

 

[sdpatt]

There is a timing belt on the front side of the engine, but no chains. The power steering pump is over there, but it turns slowly and doesn't usually have much tension on the belt so its bearings last, greater than, oh, 256,800 miles in my case. Could it be valve tappet chatter? How many miles since your last valve gap adjustment? The timing belt tensioner is on that side of both the 3.0L and 3.2L engines. They are lower on the block, just above the crankshaft damper on to the firewall side.

 

[Milo]

I listened to my car with a fake stethoscope tonight and I didnt really hear anything out of the ordinary. It must only do it when its a cold engine. The car has 126k and I have no records of repairs. I am thinking it needs a valve adjust so that could be it. Could the timing belt tensioner possibly make noise until it heats up good? If its light out when I leave in the am I will listen to it and post my findings. Scott I liked your write up on the oil pan and starter, very well done. It inspired me to do mine last saturday.

 

[Milo]

ok I listened again when it was cold and I think its coming from the firewall side in the timing cover but I can hear it thru the valve cover too. I definitely hear some tappet noise in there but the sound I am trying to diagnose has a squirrel cage sound. What do you think? Thanks

 

[Mike Kopstain]

Are you mechanically inclined? After the recent experience with SHOSPD, I would be weary of driving it anywhere until you hook up at least in oil pressure gauge to it to make sure it's within operating specs. I know this seems totally extreme and it is probably just the valves, but I'd rather not shell out a lot of money for a new engine if it is something worse. Also get that valve job done anyhow. You can also do damage if that's not done and if the sound you hear is coming from the valves/ cams you're most likely already in trouble.

 

[swemstrom]

Milo,

What year do you have? If you have a 96-99 BEWARE. Your cam shaft is ready to break. I have read over 70 cases of this happening to people myself included. I had to get a new engine. Go to v8sho.com and you can read about cam failures. I had a ticking noise that I thought was due to the cold. My engine failed coming out of a toll booth. $4,500 later I was back on the road. There is a fix some people weld it, but I also read @shoshop.com they are doing something different. Good luck

Scott

 

[Milo]

Luckily it is a 90 so no problems with the cams breaking. It sounds like a bunch of us NWerners are going to get together on the 27th to all do valve adjust. For now I will drive my truck as much as I can stand. I really think it sounds like a pulley of some kind though. Any input on bad experiences of thier timing belt tensioner would be greatly appreciated. If its most likely an impossibility that it is whats noisy then I guess it must be the valve train. Where do hook up an oil pressure gauge? That is something I definitely feel the need to do. Thanks
Aaron

 

[greensho]

Milo, I think your car is experiencing the same exact problem my car is (at least it sounds like it). The noise in my car is more like a "knocking" or "rattling" sound.

A local mechanic took apart piece-by-piece all the belts and told me it's a loose timing belt tensioner hitting against the housing.

It was due for a timing belt change anyway so I guess I'll add this to all the other parts I'll replace at the same time.

 

[Milo]

Greensho, did it get quiet after the engine warmed up? It doesnt seem like that prob would ever quiet until you fix it. Would ther tensioner bearing quiet down after it warms up? The fact that mine gets quiet seems maybe it is the tappets. I guess the sure way of knowing is to just tear into it.

 

[greensho]

Milo, actually for my car, the knocking isn't apparent when cold. The sound actually starts as the engine gets warmer. Once it starts, it's mostly sounding at idle but always at 1500-2000RPM. For whatever reason, the knocking stops (or is unnoticable) after 2000RPM.

Since I can't work on my car myself (I wished I could), I've ordered all the parts I need online (thanks Scott/sdpatt) and will have my mechanic work on it as soon as all the parts arrive.