Cylinder Misfire, Getting Worse, Diagnostic and cost questions!

[bspeed3]

Hey guys,

I've posted about this before. I've had a cylinder misfire issue, but for a while it seemed to go away. Now its back. Its been getting worse. I've pulled all the plugs and coils and I'm confident its not an electrical issue. Haven't tested compression yet... but I wanted to run these symptoms by people and see if anyone had any suggestions.

1 - Its rough on idle, and its rougher when i first start than once its warmed up.
2 - Its a bit rough driving, especially at lower RPMs, and when I push it harder.
3 - Its been getting slightly worse over the past week.

I'm thinking its lost compression, which explains most of these symptoms. Which would lead me to believe its either the gasket head or the valves. What do you guys think?

Also, if it is either of those things, what do you think I'm looking at for repairs? Anybody?

Thanks much for your help!

 

[Russm]

Might want to check your injectors and seals and ERG valve for sticking!

 

[bspeed3]

By the seals do you mean the valve seals? How would I go about checking those?

 

[Russm]

Injector seals have been known to go bad with age.

 

[MSMS3]

Do you have any engine monitoring capability? Even a simple mechanical vacuum/boost gauge might tell us something. I'd like to know what your vacuum in inches of mercury is at idle and know whether the engine is holding boost when under load. Vacuum lines, boost tubes, etc. with leaks, loose clamps, split lines or hoses, etc. can cause the symptoms you are reporting.

You need to eliminate these issues before thinking the problem may be inside the engine.

 

[bspeed3]

Unfortunately I don't have any engine monitoring capability. I have pulled CEL's on it before, and i've tried switching the coils and replacing the plug. It always says cylinder 1 misfire though, so i'm thinking its not a turbo/boost issue, as that would manifest itself in every cylinder i assume.

I took the car into a repair place near my recommended by a friend. They think its an injector or injector seal issue.... they want $750 to replace 1 injector. Of course they also said that they are only 80% sure that its an injector issue. Dont' know what to make of that percentage. $225 for the injector and the rest for labor. They also suggested I may want to replace all of the injectors as long as they have it open.


I just got a copy of the service manual so i'm going to have to figure out today what kinda labor that requires. I'd rather not pay $525 in labor for something I can do myself, i'd rather take a weekend and do it myself if only to learn the car better. Anyone here have experience with replacing the injectors on their speed?

 

[MikeHTally]

Perhaps a dose of Sea Foam?