94x4

It may be your choice of word used to describe the sound that you are hearing that is the cause of the confusion here, i.e., "clunk" when it should perhaps be "tick" and/or "slap", or even "hammer", terms used to describe the sound of the pistons contacting the head and/or cylinder walls.

Running with this..., have you checked your oil level lately?!? I ask because this type of sound usually occurs when someone is low on oil (best case scenario) or is "spinning" or has "spun" a bearing (worst case scenario).

So check the oil level and post back with what you find and we'll try to get you sorted out before Pismo.

L33T35T 4Runner

damn... i havent checked the oil level in a thousand atleast. i'll check that first thing tomorrow morning. my mechanic and i are leading more towards an engine knock. he had me replace this EGR valve (front passenger side of the engine) it just had 4 hoses going to it. it helped it out a lot, he says just throw some 91 in there and see what happens.

94x4

That's all good with the "mechanic" and all, but check that oil first.

L33T35T 4Runner

oil was fine, and im on my way home from a 500 mile road trip. truck ran fine with no problems with so ever. i threw some 91 octane in there and it helped it a little. now we're back to 87 and its back to its normal marbles in the engine noise when its at a certain RPM (around 3000-4000). i dont know what to think anymore. it runs perfect

93ToyKid

Sounds more like pinging or spark knocking. Sometimes when it's hot and I press on the gas (such as a big hill on the freeway), I get some "marbles in the engine." Usually only does it on 87 octane or crappy gas, which are the symptoms you're describing. Try some seafoam and a tank of 93.

L33T35T 4Runner

i did a tank of 91 on the way up to pismo and it helped a litle , but not much. when i got home from pismo shell was out of 87 so i filled up with 87 from chevron, no more sound, atleast i didnt hear any on the 2 miles home.

94x4

So after all of this it turns out to be nothing more than a "bad gas" from Shell issue??

Glina

Bad gas? So what is knock sensor for?

Do you have check engine lamp on or are you sure that it works?

L33T35T 4Runner

nope, its still doing it with the chevron gas, same as before. no check engine lamp, and yes it works, it went on when my speedo cable broke a month ago. i tried 1/3 can of seafoam through my valve cover breather vacuume tube while it was running. let it sit for 15-20 minutes, no change, and it didnt even smoke at all. i also put the rest of the can in my gas tank. (it was about 13 ounces to 13 gallons). still makes the noise. hopefully im selling it soon so im not too worried about it anymore, especially after it lasted over 500 miles

L33T35T 4Runner

sound went away after i adjusted my timing. i was 25 deg. advanced with the jumper installed as shown under the hood. it's supposed to be 10.