My 97 Cherokee 4.0 184,000+ miles had been running rough and the check engine light was on, so i scanned it and here is what it showed.

Stored DTCs
PO303 - Cylinder 3 Misfire
PO304 - Cylinder 4 Misfire

Pending DTCs Detected During Current or Last Completed Driving Cycle
PO300 - Random/Multiple Cylinder Misfire Detected
PO302 - Cylinder 2 Misfire.

I proceeded to do a cylinder compression test and these were my results Cylinder #1 - 150 psi
Cylinder #2 - 150 psi
Cylinder #3 - 70 psi
Cylinder #4 - 70 psi
Cylinder #5 - 150 psi
Cylinder #6 - 150 psi

What other test should I do or what do you guys think is wrong? PLEASE HELP!!!

 

Sounds like a blown head gasket. I'm no expert but you definately have a loss of compression probably blew the head gasket

 

Yeah that's what it seems like to me also.

 

There was a TSB for the valves intermitently not seating right something about spinning them to resolve its worth looking into

can you do a cylinder leak down test ? that will tell you if its holding pressure

 

No it does not. It sounds like a loss of compression on two cylinders.

One of the possible causes is a blown head gasket. There are many others. Don't jump to conclusions without further investigation, unless you enjoy wasting money and time.

OP, do you have any coolant in your oil? Do you have any oil in your coolant? Loss of coolant?

Next step: Do a test for combustion gasses in your coolant. You can buy a kit at any auto parts store.

If the test is positive, you either have a blown headgasket, blown head, or cracked block. At that point, it's time to pull the head to find out which.

If the test is negative, it's time to look at valves.