nsyr

My numbers are #1,2,4 were around 135 and #3 was 70. I am assuming this is a head gasket issue, or at least I am hoping it is. The car runs fine other than that. It doesn't smoke except a little on a cold engine. The coolant is disappearing a little. I top it off about once a month. I am due for an oil change and it is a quart low. any guesses?

2bridges

My guess is more serious than a head gasket.

A compression test with a cylinder that far off should be burning a ton of antifreeze (white smoke) or contaminating the oil (milkshake looking) or both.

If you don't have either of those issues and have that low of compression you have a problem - bent valve, broken ring, damaged cylinder wall, etc.

Won't know till you tear it down, but my money says not just a HG based on info you have given

Good luck!

nsyr

i did take off the expansion tank cap after driving it today and it sounded like air was being sucked into the tank. like it was under vacuum.

dhall615

i think that i show it is supposed to sound b/c it is a closed system. and mine makes the same sound.

hosrom_951

- Was the engine at normal operating temperature when you carried out the compression test?

- While cranking the engine, was the throttle fully open?

-On cylinder #3 (the one with low compression), did you pour a table spoon of oil in the spark plug and redo the test and saw any higher numbers?

Ian Carr

Hussam your alive?!

could be a head gasket, i know when my cylinder wall was scored it was reading about 100-110 and a spoon full of oil brought it back to normal (130s).

You could also have a burnt valve, if your pressure is that low I would expect to loose more than a little anti freeze, not to mention your car doesn't smoke much. Next time you start up your car, smell the exhaust and see if it has a sweet smell to it.

nsyr

I did the comp check after a 20 min drive. I had all the plugs out with the throttle wide open. I am hesitant on putting any oil in the cylinder. I tried that once on a subaru engine and ended up breaking the ring lands. I am going to pull the head today and I will post what I find.

Ian Carr

sounds good

nsyr

I just did another compression check right after a long drive and now all the cylinders are up in the 140 range, including the one that was low yesterday. I did have a little trouble getting the guage screwed into the hole yesterday, so maybe it wasn't seated all the way. This would explain the low reading. However, I am going to let the engine cool and check it again just to make sure.......

2bridges

BAAAWAHAHAHAHAHHAA

I hate when that happens.

Congrats man - that is a wonderfull discovery.

hosrom_951

Ja, and kicking!

Just a bit busy

You should carry the test when the engine is at normal operating temperature, not cool. Personally; i like to carry out compression tests several times such as once when the engine is cold, and trice when fully warm to get a nice range/idea of the numbers.