hey guys. over the past few months, i've noticed my JDM B16A to be knocking quite badly. I've been meaning to get it diagnosed, but have been very busy and have never found the time. I'm pretty sure it's a valve knock, but I'm not positive. Here's a description of the knock:

Cold start ups - When i first start the car up cold, the knock is very apparent and i noticed that the oil pressure light stays on while the knock is happening, then shuts off after the knock shuts off. It isn't like this on every start-up either, only on cold ones.

Slow acceleration - When slowly accelerating through every gear, you can hear the knock. Hard acceleration it disappears, applying breaks it disappears. Only on soft acceleration.

A few notes: After my car detonated a piston from being turbo'd with no tune, I went to a buddy of mine's shop to have him replace the piston. He replaced it and I noticed that the engine has been knocking ever since that day. Another thing is I read another post about how junk can get up inside of the transmission if the CV boot is torn, which might cause a knock. I noticed yesterday that my front passenger side CV boot is torn. I don't know how long it has been like that, but it can't be for too long because I had an oil change at a friend's shop a couple months ago and it wasn't torn then. Could this also be a significant issue?

I appreciate your time guys, hopefully somebody can help me out with this problem. I'm planning on painting my valve cover tonight, so while I'm doing that, i might take a few mins and check each valve to make sure that it's tightened down all the way. Lemme know what ya'll think.

- John

 

You have a turbo B16 with no tune and your wondering why its knocking?

 

i took the turbo off after the detonated piston. pretty much the turbo came off the same day the piston was replaced. ever since then, i've been n/a.

also, the knocking began after the piston was replaced so i don't blame it on the turbo.

 

I have the exact same problem, except that I have not made any modifications to my car. So you think it just needs a valve adjustment?

 

i'm hoping thats all it is. when i try it tonight 97coupe, i'll let you know if it helped or not. everybody else, more comments/suggestions are welcome!

 

Check your timing, was the piston the same pistons as the rest, whats the compression?

 

my bet is you ****ed up a bearing really good. and theres a lack of oil pressure

 

piston was the same, timing was set correctly, and 99si, all bearings were replaced when the piston was replaced, including rings as well. so i know it cant be that, and trust me, that was another thought. originally, i had no idea that i detontated a piston, i just thought my piston rings were fried. thats why i went ahead and got the new rings and bearings.

 

unless the journal of the crank is messed up slight amounts so that the bearing dosent sit flat in there.

jus because you put new bearings and everything in there dosent mean its not the culprit for the problem.

 

thats true.. damnit, i dont want to tear into the internals again. guess i really dont have a choice..