WTF Now???

[Tamatalon39]

on the way to work yesterday. My car which was running pretty good developed a miss Upon further inspection, it seems my #2 cyl. has 0 (zero) compression, now what would cause a cyl. to have no compression at all? i would think a bad set of rings. it would at least have some cyl pressure.

Now I need to make decisions. on whether I want to keep this car, as its killing me

 

[Tyeler18]

Headgasket.

 

[92tsiawdguy]

You could have lost a rocker, valve could be stuck open, burnt a valve, burnt a hole in a piston, lifters collapsed. Pull the valve cover and look for any signs of this on that cylinder.

 

[assassin3117]

Head gasket could be the issue but a burn valve sounds more likely to zero compression. do a leak down and check at the back of your car and tell us if you hear a hissing. But a head gasket could be it as well but I will lean more towards a burned valve.

 

[clipto]

Time for maintenance.Check everything over if you don't remember the last time it was changed change it.+1 on the headgasket.Double check compressions and all that fun maintenance stuff.Hope you get it fixed.

 

[shockracer]

Was your coolent bubbling over? Did your dip stick come out? White smoke? Blue smoke? Oil and coolent mixed?

 

[Tamatalon39]

Ok Well I pulled the VC and there are no signs of a lifter or rockers missing everything looks uniform. However, I bought the car off of a guy on Ebay- when the car got here I had to put a new head on it (bent valves) and I reused the copper head gasket which was brandnew.

The car did smoke some (blue) from the minute I finally got it running , so I figured that since the car sat for awhile that the rings were stuck or something, the smoke wasn't horrible. but def was there.

My coolant does not really boil but does have some pressure everytime I shut it off I can release the valve on my coolant cap and it will bubble. not sure if this means anything, somebody told me that my overflow bottle cap could be the reason for this

I guess I can pull the head and see whats up not really in the mood because it is cold out but I do like the car and it has ALOT of potential


I orig. thought the car had a bad injector but all tests led to the compression check.

 

[kmarttalon]

i try and avoid reusing head gaskets my example was a boosted mustang and i tried to reuse a cooper gasket fired it back up and started overheating replaced the old gaskets and worked fine, did it have aftermarket headstuds

 

[Tamatalon39]

yeah it has head studs and I thought the whole reason to buy a copper one was to reused and to lower compression. wiith a thicker HG

 

[LiquidX]

i try and avoid reusing head gaskets my example was a boosted mustang and i tried to reuse a cooper gasket fired it back up and started overheating replaced the old gaskets and worked fine, did it have aftermarket headstuds

yeah it has head studs and I thought the whole reason to buy a copper one was to reused and to lower compression. with a thicker HG

Never reuse a head gasket. Copper head gaskets are only good for track cars. They are an uber soft metal which needs constant head stud re torquing. The positive for the copper gasket is it will melt first before the more expensive parts.

Stick with an OEM or Felpro composite gasket, they can take a great deal of abuse.

Before you tear anything apart, double check your mechanical timing to be sure it didn't jump.

 

[Tamatalon39]

mech. timing is still good I checked that already, Guess I just have to bite the bullet and yank the head off I just hope i didn't cook the head in anyway. 6 bolt heads arent too easy to find around here

 

[CrawlinZX14]

pull your exhaust mani and inspect the valves on the exhaust side of that cyl. Then if nothing pull the intake and inspect too. Since to pull the head your doin it anyway. If nothing, I would check the cylinder. Find its BDC. U should be able to look in the CC with a flash light and see the top of the piston to see if its melted or deformed at all or scarred from a valve. Then pull your VC and see if any of your valves are not sitting up top all the way with the cams removed, or just not pressing down on the valve. You can check your lifters and rockers too. You could very well have bad valve lash or a collapsed lifter as said before.

 

[Chill Kill Kult]

could try a wet compression test which is the same procedure as a regular compression test but you squirt engine oil into the spark plug hole, the oil will temporally "seal" the piston/ring area. If you get some or better compression by going wet then the problem is in the bottom end. if it is (roughly) the same, as the dry than the problem is upstairs. Also, you can run an adapter from the spark plug hole to shop air, and pump air into the cylinder, where the air comes out will tell you where the problem is, i.e. if you hear it through the throttle body then bent/burnt intake valve, bubbles in the radiator = head gasket/warped head and so on. And make damn sure you're on the compression stroke while testing otherwise you'll make yourself crazy later on.

 

[amarin26]

0 compression in a cylinder usually indicates a bent valve allowing it to stay open.

 

[awdspyder98]

0 compression in a cylinder usually indicates a bent valve allowing it to stay open.

the above statement is correct but it could also be a melted piston.

 

[doayamaha]

before taking it all apart dump about a cap full of oil in the cylender and see if the compression comes up. never the less you are atleast going to have to get the head off but that should tell you if the rings are bad.

 

[Tamatalon39]

the above statement is correct but it could also be a melted piston.

well I took off the head, and I am missing a piece off one of my exhaust valves, I could not find the section that was missing which is weird like it just melted off. this may be possible because I have been trying to tune my car, but I have never exceeded 1200 degrees any ideas?// dont want it to happen again. I am gonna read how to remove a valve shouldn't be too hard.

 

[Chill Kill Kult]

if a small piece cracked off it could have gone out through the exhaust manifold, like if it broke off right at the end of combustion when the exhaust valve would open. might be cause for concern with the turbo, might not be. if you do hear something like a dime rolling around in a clothes dryer you should have an idea and not drive the car without further inspection.

pay close attention to the valve seats, if there is some damage (not saying there should be, but you never know) then that would need addressed as the valve has to seal properly for proper compression. Find a head shop (not the one with bongs on the shelf) and get a 3 angle valve job while you're at it (the 5 angle is bunk).