Can anyone help me diagnose this engine noise? I am in between lifters or rod knock. But after some research it sounds like it could be other things as well.

It happened the other night at the drag strip. I launched off the launch control and I spun to red line real fast and heard a big backfire. I immediately starting hearing this ticking sound so I shut her down. The noise happens at idle and gets faster as the engine revs higher. Please click on image below to see video.

Motor is an evo 9 with stock bottem end. GSC s3 cams and kiggly springs and retainers been in for 500 miles. Engine produces 500whp and 400tq on mustang dyno. All new belts, tensioners, and pulleys were done with the cam install.

http://s1103.photobucket.com/user/ma...f4764.mp4.html

 

My guess would be - not lifters.

 

Ok. Any guesses on what it may be?

 

An exhaust leak can make a sound like that. Otherwise, probably time to pull the pan for an inspection.

 

ok thanks.

Anyone else got any guesses?

 

i will drain the oil first to look for any metal flakes before I drop the entire pan.

Next step will be pulling the valve cover off to inspect the head I assume?

Anyone got any other easy tricks to diagnose?

I tried the screwdriver to the ear trick and my guess is the sound is from somewhere in the head. I could not get good feedback from the bottom end of the block.

 

The noise sure sounds more like its from the top end. Do you have a stethoscope to pinpoint if the noise is up top or lower

 

i purchased a crappy $10 stethoscope from an auto store. Do i just place it in different areas on the head and block and figure out where its loudest?

 

I hear the sound the best through the valve cover. But I am concerned that is only because its the thinnest material to listen through. When I place the stethoscope on metal parts of the head, I do not hear it as well. I am having a hard time hearing anything from the bottom end.

 

bump...still need more advice/opinions/help, please.

Thanks

 

I would start simple and pull the valve cover and check and bleed all the lifters to make sure you don't have a clogged one personally.

 

It's from the head

 

just did a compression test.

118, 120, 121, 75

#4 cylinder looks bad. Leakdown test will come next then I will pull the head.

Would the lifters needing bled be the cause for low compression or high leak down? I assume no. Lifters only cause the tick and not compression problems, correct?

 

I did a leakdown test and my leakdown was good. 6%-8% for all 4 cylinders.

What would cause low compression but still good leakdown results?

 

Oh and adding oil to the cylinder with low compression brought the compression up to 120; right with the others.

Sounds like a piston ring, correct? but why would leak down still be good?