Identify this sound?

[Klutch]

I have no idea what this sound is but I am sure it is related to my misfire issues. Could some of the seasoned people chim in? im sure someone knows what it is. Thanks!

http://www.youtube.com/watch?v=YyQVpSbEpWc

[dpzelenak]

sounded nor at first but in the revs it sounded it a lifter or maybe a valve?..
not sure

[Klutch]

I was thinking that. If you listen close at first its knocking. Just not alot I assumed the lifters moved alot. The cylinder does seem to hold compression.

[Scottydoggs]

that sounds like a rod knock and a lifer/rocker clapping away.

[Klutch]

Is there anything I can do to see if its one or the other?

[dpzelenak]

what about a piston pin knock?

[Fivefingerdeathpunch]

spun bearings would make the oil all full of sparkles, pull the dip stick and see what it looks like.

[Klutch]

I pulled the dipstick and the oil looks normal. Only has about 1000 miles on it. wiped it off with my fingers and did not notice anything in it.

[dpzelenak]

does engine temp make a difference in the noise?

[Klutch]

Nope, It is always there. its a completely stock GT I dont know what could of caused internals problems. I do not drive it hard.

[blueguy]

Well...have the LIM gaskets ever been serviced or the cooling system flushed out?

It does however sound bottom end related to me though...I would however yank off the VC's and just check to see if a rocker didn't pop loose or a valve spring didn't break. Does it misfire? If not...then that kind of rules out my last theory.

[Klutch]

LIM has never been serviced afiak. I do flush the cooling system on a regular basis. I took the covers off last night and everthing looked fine from what I could see inside. and Yes it has a horrible misfire on cyl 6anked

[blueguy]

Step 1: Remove Crap in the way of the rear VC
Step 2: Remove Rear VC
Step 3: Unbolt the ICM and crank the motor over and see if there is any strange movement on the Intake or Exhaust valves on the cylinder closet to the drivers side...or the far right if your standing in the front of the car...also...check the rocker arm/bolt to see if one or the other is loose.
Step 4: Report your findings and have a few burz

[Klutch]

Will do. do you know if anyway to crank the engine over while under the hood or am I going to have to find a helper?

[Klutch]

I was thinking about buying a auto stethoscope do you think that would make diagnosis quicker?

[blueguy]

Will do. do you know if anyway to crank the engine over while under the hood or am I going to have to find a helper?

Yup...like I said...unplug the ICM...I think its either a 7 or 8mm bolt that runs into the bottom of the coil pack bracket.

You can crank it all day long...and with no spark it won't fire...I'd either set up a camera to watch what is going on...OR...have a buddy crank on it while you sit there and inspect it.

I was thinking about buying a auto stethoscope do you think that would make diagnosis quicker?

Negative...use a long dowel rod or a long screwdriver...they work just as good.

[tgarison]

that sounds like a rod knock and a lifer/rocker clapping away.

I agree that sounds like a rod knock to me.

[Klutch]

I am going to test the valves tonight when my friend comes over. If it is rod knock I am assuming my only options are rebuilding or swapping in another motor?

[blueguy]

Swapping in another motor would be cheaper...L36's are a dime a dozen. While the motor is out I would at least suggest a downpipe on that thing...even stock GT's tend to knock from the factory...which is pretty lame for a N/A car.

[Klutch]

I haven't had a chance to test the valves yet but I did swap my injectors around today to see if my misfire followed and it didn't. Which really makes me think its in the heads. I tried bluegtp91 trick of using a screwdriver as a stefanie stethascope and sounds normal when I put it on the valve covers and the oil pan but it really loud uff I put it directly on the head. My question is what could be wrong with the valves if it has compression?