Ok, ive listened to may engine again and got a friend to listen to it too. My tC is almost 2 years old and the engine is making loud noises. Like a shifting noise, it sounds like the pistons are moving up and down noise. Ive used gas line antifreeze and concentrated cleaners in my gas. like Techron. I just dont know what to do, even if its been warmed up its the same. Maybe this can be fixed or replaced under warrenty or somesort of lemon law?

maybe injectors are clogged or no oil, or something? I added a motor oil additive to help prevent thermal breakdown and keep parts lubercated when the engine is off for a while. ???????

 

Well, first, we need to know the noise and exactly how/when it occurs. Pistons do move up and down obviously, so I am guessing you are saying it is knocking? If so, most of the time "knocks" are mis-diagnosed at first.

If it is a knocking noise, when does it occur? Does it do it worse if you feather the throttle around 2500 rpm?

Does it do it worse right at start up?

Does it match engine speed or is it 1/2 engine speed? Or is it a random clatter (which could be piston slap or valve train noise depending on how and when it occurs)

As for warranty, that depends on if you still have warranty left. Lemon law only applies for the same issue happening again and again and the dealer not being able to fix it. This is simply an issue (if it truly is an issue at all)

As for additives, I recommend none. I run BG44K around 60- 80,000 miles sometimes to clean the fuel injection system, but that is it. I run Mobile 1 changed about every 4,000 and keep the other fluids changed and checked as needed.

But again, you need to give more description on the noise you are talking about.

 

i wil try to get some vids with audio this weekend. i think its a knocking sound. its right at startup/ sounds like something is being slapped. at a constant pace.

 

Its probably the knock your hearing, kind of like a repetitive ticking right? By the way, the pistons are moving up and down but no need to be alarmed, its just the way an engine works

 

The trick is to make sure it is indeed a knock. I have seen people diagnose everything from noisey valvetrains to damaged clutches to even a chunk of a belt or pulley missing as a knock.

I have seen a lot of toyotas clatter pretty good for the first bit after starting when people switched to a heavier weight oil. So all the little details need to be known before we can make an educated guess.

 

Sounds like that are often caused by a spun rod bearing. If it is then the best thing to do is STOP driving it before the crankshaft gets damaged and it may be able to be repaired for a lot less cost than if the crank gets damaged. You should also have the oil changed and check what drains out of the engine as well as have the filter torn apart and checked for metal contamination of worn metal particles. An oil pressure check would be good too.

 

Lets not jump to wild conclusions though either before hearing what is going on. 99% of the time I have heard people say they have a knock, they do not. And a spun rod bearing will make some BAD noises. The crank is already trashed if that is the case. That will cause a very bad knock very quickly that will not go away.

If it is a "wobbling" type noise that is more random in nature (doesnt keep perfect time with the engine speed) and tends to go away after 15 min or so, it could possibly be piston slap (collapsed skirt).

If it is a lot of clatter for the first couple of seconds only, it is most likely valve train noise. This can be too heavy of an oil, or a number of other things.

If it keeps a nice, constant rythym, is a deeper knock and seems to follow crank speed, then you could have an issue on the crank (rod knock). If it is the same, but is a double knock, it is getting bad. Usually a rod knock will be more predominant if you hold the throttle at about 2500 rpm, then feather it up and down.

If it is the same as above, but seems to be 1/2 crank speed, it is on the cam.

If it sounds more like a pencil tapping on a table, then it is also most likely in the valve train.

If it is a spun bearing, then oiling stops immediately, the crank is damaged terribly right away, and you wont drive very long at all.

But, like I said, a lot of "knocks" turn out to be something else. I dont recommend driving it if you are unsure, but dont panic either until it can be checked out.

 

thanks, its like a contant ticking kinda sound.

 

There is a ticking (not too loud, like a click) normally, which is the Vaccuum Switching Valve. If you listen over near the MAF on the intake you will hear it well. It may be something else, but it never hurts to check the simple stuff. If that is it, it is completely normal.

If it sounds like it is definitely coming from the engine, then it would be a good idea to take it in if its under warranty. We can try to make educated guesses here, but if you are under warranty, then it would pay to take it in if you have eliminated the little stuff.

 

yeah, there is a ticking from the MAF area, but this one is deff from the engine. if its still not snowing up here in maine sat, i will try to get a sound clip or vid, but it might be hard to hear, its def from the engine like a fan tick slap noise. thanks. i'll call bout tuesday for a app. i need to get that airbag recall done, and check to see if my tanabe muffler will pass inspection and if i could get a certificate that offers an "A OK" for it.

 

Hey good idea to check the belt in case it is breaking apart or has a dead animal stuck in it . . . lol and you can drive a long time with a spun rod bearing - I did with my first car - the fact that it is noisy when he first starts up may indicate an oil pressure related problem.

 

This is what happens when you spin a bearing:

https://www.scionlife.com/forums/vie...=asc&&start=60

It doesnt take too long. When one truly spins, the oil passage is blocked and you are running metal to metal. You wont drive very far that way.

 

Man that engine was cooked!! the right most rod bent and they all show signs of overheating at the crank journal - pistons show some heating signs too. Was that thing turboed?

 

Supercharged I beleive and running an undampened crank pulley. I dont know if they ever pinned it to an exact cause though. There is a bunch of info on that thread. Bearing spun, oiling stopped in the journal, near seized righ there and twisted the rod, then of course the rest of it went to crap And I am sure it made some cool noises as well!

 

Would putting an undampened crank pulley cause some sort of random knocking? I don't know if the car made this noise prior to me putting the Zpi Crank Pulley on. Yssterday when I had my hood opened, I hard some sort of knocking noise from the engine compartment, I couldn't pinpoint where is was coming because it was really random. The noise went away after awhile. I dont know if it's the crank making that noise due to it not have the Oem heavier crank pulley. Any of you heard this noise?

 

Check for an abnormality in the pulley like a chip. Or a tear in the belt somewhere.

 

i have the same issue... really loud knocking sound.. my cars sounds like a diesel truck. i went to the toyota service. they said no problem.. its only a backpressure!!! (????)

here is the video: http://www2.djn-ice.com/CSOCSO-SUPRA/weirdsound.wmv

oh and the sound gets faster as i speed up.

 

They said the sound was "only backpressure"?????

Cant hear the clip here at work though. But if it were my car the part would come off if I couldnt figure out what was going on.

 

I say just take it in! Do you have warranty left?

 

WOW that is noisy - sounds like valve and timing chain noise - a rod knock is deeper and more hollow sounding. If you change your oil and the sound gets quieter then you probably should be looking at pulling the cam cover off and checking valve clearances - first would be a compression check though to see if all cylinders are equal and up to spec. Wouldn't hurt to check for an exhost manifold leak too. Next time you record - throw a gentle rev on the engine so we can hear it accelerate and deccelerate.