I've already adjusted the valves and rechecked twice. Its only audible about 2500 rpm or higher, Is there anything else in the engine which can make the same noise? I can;t think what the problem might be.

 

Timing chain slap, noisy injectors, exhaust leak. That's all I can come up with.

 

what oil filter do you use
if its not a toyota oil filter u will have probs
there is a check valve in the factory filters that keep the tentioner tight
i found out the hard way 2 years ago also check the guides make shure they are still in good shape
also check your timing cover whaen the guides get worn to bad and the chain gets slack the chain will eat away the timming cover and cause it to expose the water jackets making you to think you have a blown head gasket

 

I looked at a $3 Fram filter and a $11 Mobil-1 filter and didn't see an 'anti-drainback' valve. I saw a bypass valve that let oil around the filter if the filter was plugged, but no anti-drainback valve. The anti-drainback valve, it it is in the filter should block the center/input of the filter so oil didn't run back down the feed. Neither one had it.
I'm kind of guessing the mobil-1 didn't have it 'cause I poured about 1/4 pint of oil into the center of the filter and nothing came out when I turned it upside down... presumbably because the filter media had soaked up the oil and I could see the filter media looking up the center of the filter and down the 'output' ports as well.

 

well im not compleatly hure how the toyota filters are internaly difernet that aftermarket filters buy i do know that toyota filters should be used
they help prevent the timing chain slack and damage to the chain cover

 

It doesn't sound like a timing chain to me but I'll take me stethoscope to it. I use a Wix oil filter. I'd be curious to see how an filter prevent timing chain noise. I'll replace the filter today. I replaced the timing chain three months ago.

Would injector noise change with throttle position, or rpm? That might be a possibility.

I don't think its an exhaust leak because its not dependent on load. I could be engine braking or flooring it at 2500 rpm and the noise is the same.

 

Considering the injectors fire all at the same time, on every revolution and stay open longer when the throttle opens...
It's probably an EGR passage / exhaust leak.

 

I think its either valves or injectors. I just started it one day and it was there.

I'm certain its not an exhaust leak. I've had those before and the noise associated with a leak is present when the throttle is pressed down and silent when engine braking or coasting.

My understanding is that the EGR operated when the engine is hot. My noise is present the moment the engine is started

I listened with my stethoscope to the valves and none seem to be loud, though when I put the stethoscope on the nuts that secure the valve cover, some are louder than other nuts. The injectors sound loud when I put the stethoscope on them, but they all sounded roughly the same. Would injector noise come on this suddenly? What would cause this? How would I tell it was an injector?

 

How tight do you tighten your nuts? How much should the rubber grommets on the valve cover be compressed? I don't think I've over tightened them as I've done this many times, but who knows.

 

Anyone?

 

Sure it isn't just pinging?

Btw, the nothing but toyota filters comment is complete bunk.

 

In the last little while, here what I've done.

1. Set, reset and checked the valves, they're fine.
2. Fixed the speedo (unrelated)
3. Set the timing (maybe?)

It pings a bit, but always has. Set to 10* BTDC.

 

I bet you are over tightening your valve cover. If you do, it pulls up on the rocker assembly increasing valve clearances. Common mistake.

 

i set my valves cold at 7-11. i use a 8-12 feeler gauge to check that they are not loose. if the 8-12 slide in they are loose. somebody on here a few months ago had a problem with an over tightened valve cover, but it made noise even at idle. when you replaced your t-chain did you replace the tensioner as well? does it run rough?

 

Valve cover bolts should be a little more than finger tight at 43-60 inch/lbs. I just did my valves and so far so good.

 

I didn't know it pulled up on the the rocker assembly, interesting.

 

I'd like to know how that happens considering the studs for the cover are right next to the head bolts.

 

both of the above mentioned filters have anti drain back valves. the fram one isnt well made and tends to leak. the anti drain back prevents oil from within the filter draining back into the crankcase while the engine is off, which prevents dry starts. It wont kill the timing chain, or make excess noise, except for the few seconds after startup.

The valve noise/exhaust leak noise are pretty distinctively different from each other. get a long screwdriver, and place the pointy end on the top of the valve cover, and the handle end up to your ear, with the engine running, and you can use it like a stethascope to pinpoint the cause of the noise

 

I think its injector noise. I loosened off the valve cover to no effect. Is cleaning the injectors difficult? Removing them?

 

if that's what you're suspecting, mine made more noise after removing and cleaning them, lol. probably because I removed 1/8th inch of dried up mud off of each which was sort of suppressing the noise in the beginning I guess.