Weak compression numbers? What do they mean?

[Outdorsman]

Well I've been having issues and my car is once again dead. I compression tested it using a crappy autozone gauge and got these terrifying numbers.

120 0 0 120


What do they mean? Bent valves? It was on a cold engine dry test

 

[007jimmy]

Could be bent valves or blown headgasket. What are the "issues" you are having?

 

[Outdorsman]

It studders, hesitates, and dies. You can't keep it on when you start it. It idles at 500 rpms and sounds ike shit. It eventually dies. Gotta kkeep pressing the gas pedal to keep it on. When I was driving it when this occurred, it began to shake and lost all power, it doesn't want to move anymore when you put it in gear.

 

[destruckeclipse]

Seeing as how two adjacent cylinders have no compression you could be lucky and just have blown the head gasket.

Time to pull the head and see what you find.

 

[Outdorsman]

If it were the headgasket, is it possible to be blown with no symptoms? I never saw white smoke unless it was in the morning where it was cold. Also, it never over heated as far as I know. No coolant in the oil either, and vice versa.

 

[levimits]

I had compression results like yours when my car jumped timing and bent some valves, so I would check and see If the timing marks still line up.

 

[Outdorsman]

One last thing, when I tested it using the compression tester, I heard a noise as if air was escaping. It only happened when the gauge was connected in cyl 2 or 3. Every time I cranked the engine for the tester, it sounded like air was escaping. But like I said, it only happened while the tester was connected to cyl 2 or 3.

 

[Scoobystyl]

Something happened with the valves on cyl 2-3 pull the valve cover off and inspect everything, its possible the rocker arms popped off, thats best case scenario worst case is your valves made contact with the pistons and knocked holes in them, not likely but possible but could happen

 

[Outdorsman]

Well I can't afford to dump anymore cash into this vehicle, I'm just going to sell it as is... Probably put a down payment on another car with lower mileage and whatnot.

 

[BogusSVO]

Sounds like you have a compression blown HG, You will not get white smoke or mix water in the oil.

120 0 0 120, and you hear air escaping when the tester is in 2 or 3

Have the head checked and surfaced, and a new composite HG, You should not need much more than that.

 

[BogusSVO]

double post

 

[Outdorsman]

yea its definitive, its a blown hg between two cylinders. What a relief. I thought it was something even more serious. I researched more and turns out a couple other guys had the same symptoms I have. Will follow what you instructed Dale! Thanks! Time to upgrade to some ARP headstuds