Compression test results have my head spinning.... Please help.

[Red98CobraStang]

Hey guys. Got around to doing a compression test on the cobra today. As some of you know I purchased a 2.3 whipple 03 cobra about 2 weeks ago. Long story short I've been having problems ever since I purchased it. Had a vacuum line pop and popped the FRPS shortly after I got home on a test drive with one of my buddies. Since then, been nothing but down hill. Pulled plugs, and found cylinder 7 full of oil, and the plug saturated. However, the compression test has me wondering WTF is wrong....

Cyl 1 - 160
Cyl 2 - 160
Cyl 3 - 160
Cyl 4 - 160
Cyl 5 - 160
Cyl 6 - 160
Cyl 7 - 150
Cyl 8 - 155

These were all measured cold, letting the car crank over 4 times. Sooooooo, what gives? Car smokes on start up when warm. When running, and idling, I can blip the throttle and I get a healthy puff of smoke out of the exhaust. I can hear a small noise, sort of a ticking, coming from the oil pan. The noise is more pronounced when cold, and gradually gets quieter as it warms up, but never fully goes away.

What's everyone's opinion on whats wrong? I'm at a loss here and have no idea what to think.

Here's some pictures of my plugs. From left to right they are cylinders 1-8. These plugs have around 25-50 miles on them. Literally new.

 

[Mystic03]

Sounds like guides went south?

 

[Red98CobraStang]

That's my thought, but what's the clicking in the pan? Pieces of the guide? The engine oil was changed as well after all this happened as well. Didn't see anything in the old oil. Currently has 7 quarts of synthetic 5w20 and a Motorcraft filter on it. Maybe I'll drain the oil again through a screen and see what I can find.

 

[SVT_Troy]

have you done a leak down test?

 

[R.D.P.]

have you done a leak down test?

This ^ The test will likely show a significant problem on #7. Does the car have a head cooling mod? If I personally pulled a plug and found a cylinder full of oil I wouldn't start the car again, the head would be coming off. Hopefully it's just a problem with the one head.

 

[hotcobra03]

Are the valves black like plug when looking into head?

 

[03cobra#694]

Was there any miss when driving?

 

[Red98CobraStang]

There's a definite miss at idle. Driving the car it runs like normal until it goes into boost. I've only driven the car once after the issue. I will be pulling the head Thursday/Friday. I'll perform a leak down test today and report my findings.

I can't see the valves because I haven't had the cover or head off yet to look. You can't see the valves by just looking into the plug hole, can you?

 

[Nightmare302]

Leakdown test is the only way to know for sure what is going on. Until then everything is just a guess.

 

[badcobra]

That plug looks fouled out by fuel to me, not oil. Send your injectors off to get cleaned and flowed. See the below thread for info, it costs $50 only and well worth it.

http://www.svtperformance.com/forums/showthread.php?1019900-Bosch-105-Questions&highlight=eric+derr

 

[03cobra#694]

^^^That's where I was going with my miss question.
He also states that it's smoking though.

 

[badcobra]

An injector stuck open will cause all kinds of problems. I would get em cleaned and flowed before I start tearing the engine down.

 

[hotcobra03]

There's a definite miss at idle. Driving the car it runs like normal until it goes into boost. I've only driven the car once after the issue. I will be pulling the head Thursday/Friday. I'll perform a leak down test today and report my findings.

I can't see the valves because I haven't had the cover or head off yet to look. You can't see the valves by just looking into the plug hole, can you?

I had 2 threads open..the other had intake off..my bad..


I recall having plugs like that...wet and black

coils going weak can be cause...trying a complete set for testing is free...I found a member local that had a good known set..

weak coil might not trigger misfire code but it will make drivability issues

 

[Red98CobraStang]

The cylinder was full of oil when the engine was hot last time I pulled plugs and took a peek inside. Today, cold, when I did the leakdown test, no oil was present, but the piston was definitely black, and full of soot.

Anyways, I did a leakdown test on all cylinders, and cylinder 7 had a 30% higher leak rate then the other cylinders. I picked up a gauge from harbor freight on my way home from work. Probably not the most accurate gauge, but served its purpose I guess.

After hooking up the leakdown gauge and zeroing it out, I hooked up the gauge to cylinder 7 and it showed 75%, the rest all showed 50%, which seemed extremely high to me, but what do I know, first time doing this.

Once hooked up to cylinder 7, with it at TDC on the compression stroke of course, I could feel and hear air coming from the dip stick tube, and oil fill on the drivers side head. I could even feel and hear some coming from the passenger side valve cover vent tube.

Soooooo, the big question. WTF does all that mean? valve issue? ring issue? both?

I could NOT feel or hear any air coming from the throttle body, or out the tailpipes. Nothing from the coolant expansion tank either. Help me out dudesssss.

Is it possible that I jumped timing somehow and bent all valves slightly? School me please.

 

[SVT_Troy]

If you feel/hear air coming from the dip stick you have bad rings my friend. Better tear it down now before you cause more damage. Sucks but it is what it is.

 

[Red98CobraStang]

**** me. That's what I feared. Looks like a reman from automation is being purchased.

 

[cj428mach]

I'm with some of the other guys that looks like fuel not oil to me.

 

[hotcobra03]

Was engine cold for leakdown...just asking I never did one before...just basic compression

those numbers cold are good...the 2 low readings can just be gunk..

test should be done hot...I think results would be closer

 

[R.D.P.]

Sorry to hear about your bad luck OP. You might as well pull the head at this point. Post pics when you do. Also - head cooling mod? Does it have it?

 

[Nightmare302]

Compression test doesn't mean a thing. If he has air coming out the dipstick tube then he has a either a dead piston or ring. It might be worth taking the head off or using a scope to double check that but it sounds like you've got a hurt shortblock.