ekim121

Hey, I have a really funky sound coming out of my engine, so I was hopin' some of y'all could help me out. First of all, some background as to what's happening while this noise is going crazy. While it is making this noise the oil pressure is good, there are no warning lights, it runs well with good power, there is no smoke, and the idle is right where it should be. With that said, the noise seems to be coming from somewhere within the engine itself. It sounds almost like the sound of hissing or whooshing air. I listened from right above the engine and from best as I could tell it's coming from just under the rocker cover and sometimes it seems to be coming from the front of the engine. I'm really not sure where to start because it isn't affecting the vehicle in any noticeable way other than the sound itself. I was going to take the rocker cover off later and look down in there with a flaslight and make sure something in there loose, but I have no idea what it could be. Thanks for any insight you could give me.

ttr125mar

When does the sound happen start-up, after its warm, when the brakes are depressed, or gas is given to it? If it sounds like just air I would start by checking vacuum hoses (vacuum leak maybe) also near the brake booster.
Tell me if that helps, but usally when this is the culprit it does it when the brakes are applied.

Thanks,
Mario

85badger

how about the timing chain slapping around? Changed it lately?

ekim121

It happens when the engine is warm. It is sort of strange becuase it seems as though it won't make the noise when it's idling, but if I rev then the noise commences when it gets back to idle.

I am concerned about the timing chain guides, but I just had the head off 3k miles ago and it seemed to be in really good shape, although I'm definitely going to look when I take the rocker cover off. What exactly should I be looking for? I was under the impression that I should look to make sure the guides are there as that was the weak point. I would think if there was slack in the chain that it would run like crap. But, thanks for the initial comments and any more are certainly welcome. I'll update when I can.

ekim121

So I went out and and listened again and I think I've narrowed it down. The sound definitely occurs weather the engine is warm or cold. I would also say that it's a squealing sound which makes me think it's a bearing of some sort. There also seems to be the smell of rubber or something like that burning. All of this is making me think either the starter keeps running after the engine is going or a bearing is out on the alternator/water pump. The thing that makes me think it's not the water pump or alternator is the fact that I still have good voltage on the gauge and it's not overheating at all. Anyways...suggestions please...

bike4miles

My timing chain did this to me even though the guides were still intact. the last guy put the upper gear on backward so that could have been part of it.

93Toyota PU

could be belt tensioner pulley...they squeal when bearing is bad. If it is the water pump, it may not overheat right away...until the pump bearing gets worse. Try to narrow down the source of the noise with a mechanics stethoscope.

ekim121

For anyone who was wondering, the correct answer was idler pulley.