Cylinder head noise!

GsXtUrBo98 · 04-04-2009

I got my car running and It idles fine but when you give it throttle the cylinder head makes a hollow thumping noise....

I just installed bc 272's and did arp's along with the timing belt, ect....

I don't know what this is.. Is my head shot?? It still idles fine and runs good. It just makes an anoying noise and gets louder as the rpm's go up..

Any help on this would be great... I'm so depressed about it

4g63tcrazy · 04-04-2009

Hollow thumping noise? Could you explain that better? Are you sure you're oil is full?

GsXtUrBo98 · 04-04-2009

Quote:

Originally Posted by 4g63tcrazy

Hollow thumping noise? Could you explain that better? Are you sure you're oil is full?

Just hollow thumping... Also there is full oil in there..

I'm not sure how to explain it over the computer besides its hollow thumping that speeds up with throttle and gets louder as it goes, but it sounds fine at idle..

4g63tcrazy · 04-04-2009

Well if it runs and drive's fine just take the car for a drive. See if the noise is still there. Just make sure to pay attention and stop if anything wierd starts to happen.

GsXtUrBo98 · 04-04-2009

I did take it for a drive and it ran and drove fine...

4g63tcrazy · 04-04-2009

But the sound is still there? Are you sure you're not going crazy? lol

sleepydsm · 04-05-2009

I heard it. It's more like a loud knocking. Loudness and rhythm increase with RPM.

GsXtUrBo98 · 04-05-2009

I dont know what this is...! Tomorrow I have something going on till mid afternoon and then I'm gonna pull the vc off and see if anything is visablly wrong.

If anyone has any knowledge about this please lmk.

GsXtUrBo98 · 04-05-2009

Bump for a mitsu member in need!

**4seasons69** · 04-05-2009

it kinda sounds like you might have a collapsed lifter

deadeye · 04-05-2009

Thats what I was thinking too. DSM lifters pretty much suck. Even new ones can be a problem. I guess pulling the V/C will shed more light. Maybe something is hitting the inside of the V/C? Like a socket that got left in there or something?

tpunx99GSX · 04-05-2009

Check for crankwalk. That sounds exactly like what mine just did a couple months ago. The noise quieter until after 2500 rpms, then it would get louder or until the car warmed up, Also the car ran fine except the knock sensor was pulling timing after 3000 rpms due to the noise so it was losing some power. I tried everything to get rid of the noise and it ended up being the main bearings and rod bearings.
None of the usual signs of crankwalk were there, such as the clutch pedal dropping to the floor or anything along those lines.
I was having a hard time pinpointing the noise, at one point it sounded like it was coming from the transmission area, so i changed the clutch and checked everything. Still the noise was there.
Changed out the lifters to the no tick ones and bled them, noise still was there.
Retorqued the head, and cams. Still there
checked the CAS.
Then finally pulled the oil pan and found the rod bearings were completly fucked, and the main bearings were pretty much out of spec. I ordered rod bearings from MAP but it was too late. I drove it to a meet and on the way there complete crankwalk, Then i parted out the car.

**4seasons69** · 04-05-2009

considering he just put cams in and because he described it as a "hollow" sound and it sounds like it's in the upper part of the engine it sounds like a valve train noise. valve train noises are usually a hollow sounding noise. one thing to listen for is does it sound like it's at crank speed or a little slower? valve train noises are at 1/2 crank speed.

**4seasons69** · 04-05-2009

if you want I can come help you pinpoint where it is and what's causing it. just give me a call

tpunx99GSX · 04-05-2009

Quote:

Originally Posted by 4seasons69

considering he just put cams in and because he described it as a "hollow" sound and it sounds like it's in the upper part of the engine it sounds like a valve train noise. valve train noises are usually a hollow sounding noise. one thing to listen for is does it sound like it's at crank speed or a little slower? valve train noises are at 1/2 crank speed.

Mine sounded like it was in the head as well. It had me very confused, I pulled the valve cover like 10 times thinking it was the lifters or the cams. Checking shaft play doesnt take long and would be good to do no matter what.

**4seasons69** · 04-05-2009

Quote:

Originally Posted by tpunx99GSX

Checking shaft play doesnt take long and would be good to do no matter what.

true it wouldn't hurt to check.

did you listen with a stethoscope or just by ear?

GsXtUrBo98 · 04-05-2009

Just by ear... and trust me you can hear it!.

4g63tcrazy · 04-05-2009

Pull the valve cover off and take a look.

tpunx99GSX · 04-05-2009

Quote:

Originally Posted by 4seasons69

true it wouldn't hurt to check.

did you listen with a stethoscope or just by ear?

I was using a piece of rubber hose to try and figure it out. I even had another guy come over and make sure i wasnt going nuts. He said it sounded like it was in the head as well, almost like it was coming from the CAS. But as it turned out it was rod knock on the #4 cylinder mainly.
Kinda wish i would have found this before putting more money into it, oh well, i still have the Stage 4 Competition clutch for sale if anyones interested. LOL

GsXtUrBo98 · 04-05-2009

Just did and everything looks good...

It never made this noise before and when I parked it it didnt make it either...
I put cams and arp's along with new timing components and now it does.
The cams were all torqued to spec and so was everything else...
Timing belt was dead on with every tooth.