Hi guy. I need some help. Having a misfire on cylinder 4 in my 2000 chevy blazer 4.3L 2WD. I have spark and fuel. Compression is only 60 psi. Not sure where to go from here.

 

60 PSI is way too low. How many cylinders? Have you done a wet PSI readout?

 

Yep, way low. Might be a burnt valve. This if the case, is usually do to crappy gas.

 

It has 265000 miles on it. I've had the truck for 7 years. Fortunately I haven't had to tear the engine down that far yet. Tomorrow I am going to take the head off that side. If it is a burnt valve is there anything in particular that I should be looking for or any handy tips you recommend?

 

Do you think running a couple cans of sea foam threw it might fix it?

 

If it is a burnt valve, and what I read of your post, I suspect it is. If you have a shop air supply that you can put compressed air into that cylinder, and again I suspect a burnt valve, probably exhaust you should be able to hear air in the exhaust. Sea foam if you wan't but a burnt valve requires a valve job.

 

Thank you for the insight. I will hook the air supply to it and start there. When I am listening for the leak should where should I be listening and more over where should the distributer be pointed to a closed exhaust valve on cylinder 4?

 

Yeap, burnt valve, and/or jammed-up rings. Might as well pull both heads as they are both headed south.

ARCO (and cheap gasoline) Gasoline. Pay me now or pay me later, Junk gasoline that allows for deposit build-ups. Same with engine oil changes. Who in **** needs an oil change sensor. When its BLACK it's too late.

Someone will be making money even if the OP does the work himself. (getting tired of all the female names men use here too.)

 

You cannot repair a burnt valve with seafoam or Techron. It's gone and you need to have your heads replaced. One valve won't cut it.

 

I will do the wet test today to see if its the rings. Can I change the one head now and the other later? Things are tight right now.