Cylinder problems?
 

I thought I wounded a head gasket recently. Number 2 cylinder had the plug come out quite dark, not sooty but dark.
When I got home I did a leakdown test and all cylinders looked good ( from 3% to7% number 2 was 5%). I pulled the fuel rail and put pressure to it to see if the injector was dripping, Looked fine.
I'm going to swap injectors to see if the problem travels.
Anybody got any other Ideas?
The car is of by .015 or more in the short times leaving real lazy, and down a better than 3 tenths in the quarter.
Here's a picture of the plugs. After 2 runs and loading it up.
http://i203.photobucket.com/albums/a...ps1b05fb15.jpg

Re: Cylinder problems?
 

Could the oil filter coming off have hurt something and its just manifesting it this way?

Re: Cylinder problems?
 

I don't think so. I made 4 runs after the filter came off. I still had some oil (2 quarts) in the pan. If I hurt a bearing and bent some valves I would think it would show up in a leakdown test.
Don't know how else the loss of oil would hurt it.
I'm pretty sure the car slowed in the eliminator at Gainesville before Belle Rose. First round at G'ville I dialed it soft in full bracket mode and it was about 2 tenths off what I had figured.

Re: Cylinder problems?
 

Art, did you do a cranking compression check? That might be a tail tell sign. It is for me.

Re: Cylinder problems?
 

Just did one. They are all pretty close 1=285,2=272,3=272,4=265. I know these numbers seem high. But with the hydraulic lifters that's what it has been. I tried to adjust the cam overlap to lower it and slowed down a bunch.

Re: Cylinder problems?
 

Art.....did you run it yet with a new set of plugs ?.....the reason I am asking is, there is a LOT of anti-seize on the threads and it would only take a very small amount to actually push ahead of the threads and contaminate the plug like that......


D L Rambo.....Stk 1300

Re: Cylinder problems?
 

Put new plugs in same thing in same hole.

Re: Cylinder problems?
 

Time to take the head off and look.

Re: Cylinder problems?
 

What else on the ignition system for this hole? Wires, coil?
I had a plug boot with a crack that did a plug like this one time. Not a dead miss, but not full burn either.
Just guessing.
Good luck.
Ken

Re: Cylinder problems?
 

Changed plug wire when I changed plugs.
I'm going to switch injectors and see if I can change cylinders. If not. The coil is the next thing to change.
I don't want to pull the head just yet. Once I do if it is something else I'll have to find it after it goes back together. Want to try the easy stuff first.

Re: Cylinder problems?
 

Artie, I would swap the front two injectors, and if that isn't it, and if it has individual coils you might swap those too.

Good luck!

Re: Cylinder problems?
 

That is on my adgenda for tomorrow. I've already swapped the injectors. If that isn't it I'll swap coils. They are stock GT Cruiser injectors and stock LS1 coils.

Re: Cylinder problems?
 

Antisieze will foul a plug, You might be better off putting some grease on the threads. That's how it was done at the last import shop I worked at anyhow.

Re: Cylinder problems?
 

Art,
If ignition,fuel OK, I would check for valve leakage w/ rockers removed and header,use shop air full pressure and cover intake and ex ports w/hand to feel for leakage,this will show problems that a normal leak down or compression test will not show.
We have even went as far as spraying soap in runners to find valve leaks,it sounds like overkill,but I have found LOTS of guys problems that way after they have changed every thing in ign.and fuel system and have ran out of parts to change and gave up,when they had valve leaking slightly.
A compression issue will cause rich cylinder.
Another ideal is if computer had problem causing injector to spray too much or wrong time.
Have seen computer cause one injector to act up.
Could've damaged lifter if lost oil to lifter during oil filter problem

Re: Cylinder problems?
 

When I did the leakdown test. The air that leaked seemed to be leaking past the rings. opening the oil fill cap changed the sound.
I'll double check the fuel and ignition functions in the ECU. The fuel is sequential so I could have had a glitch.
I can also adjust the timing in each individual cylinder. I had a spare ECU but didn't ever use it so I sold it a couple of months ago.
If the next few things don't locate the problem. I'll pull the head, and do a cleanup on the valves and seats.

Re: Cylinder problems?
 

I think I found the problem. I changed injectors. No change.
I swapped the coils and was able to foul a different cylinder. So that's probably my problem. I have a coil tester in my trailer, with my spare coils. I'll ride over there and get them later today. I'd like to know if the coil testor will show the problem.

Re: Cylinder problems?
 

Congrats Artie! Sounds like you found it.

Re: Cylinder problems?
 

Yes I hope. But I want to see the coil tester confirm it. So I can check them from time to time.
The first time something happens it's bad luck.
The second time the same thing happens . It's stupidity.

Re: Cylinder problems?
 

Art,
That Sat one of the first questions I ask was is the coil dead?? I thought you said it was alright and still firing. OH! Well. Maybe I just thought you said that.
Glad it wasn't the head gasket. That dead coil makes a cyl "Fuel Rich". When the coil fails it could have pushed the gasket around or hurt a ring pack. Better go back and check that leakage after you get it running/firing enough to clean the excess gas out of the cylinder/ring pack. I did enjoy the Sat afternoon Chat!! Thanks for calling. Good luck.

Re: Cylinder problems?
 

I sort of conviced myself it was a headgasket problem. I'm used to the old if it fires the coil is fine age. I didn't even think about the fuel injectors or coils.
I bought a coil tester a year ago now I'll get a chace to see if it works. I moved that coil to another cylinder and ran the motor (no load) at various rpms. That plug wound up darker.
I didn't get a new set of plugs and change that coil yet. Will get on that Monday.
If I've got the main problem solved. I've still got to drop the pan and at least look at the rod bearings. There are over 400 runs on my Bill Miller rods. If the bearings look beat I'll replace the rods also.
Then I'm going to tackle the trans flairing for the umteenth time. Going to put a gauge to check line pressure. Shift at 7000 flairs 1,000 rpms shift at 7700 flairs 700 rpms.
Got to have it right for Atlanta.