96civicdx2o3

Just did another compression check 160/160/150/0
(Hf)Leak down test 90% leak on cyl 4, and it's about 20-30% on the others, couldn't find where the leak was coming from, the sound was really faint. Cel codes po304 p1399 sometimes p0302 and 1300 don't know what's going on but my question is y would that cyl have no compression?
Things I've done spark plugs, wires, valve adjustment, fuel filter, swap dizzy, and Iam loosing coolant which is causing my car to overheat ??? Also #4 spark plug looked rusty compare to the other ones

boostedxcivic96

rings might of let go or could have a crack an its not building compression or might need to resurface your head an a new gasket

96civicdx2o3

So a bad headgasket would cause no compression in that cyl? I was thinking if the rings are bad wouldn't I hear a knocking sound? Should I just pull the head and inspect it?

Deksinjo

Every time when you remove even ok head is best to put on inspection, maybe is just gasket is burn between cylinder 4 and coolant pipe but also check your head and is be good to give just little machine flattening.
What's engine code, do you lose coolant out engine block or engine oil level is increased, are coolant pipe is hard unusually ?

Former User

Did the timing belt snap or strip?

Redo the cylinder leak down test with a higher pressure/rate of air flow. This is the best way to know the cause of compression loss prior to tearing down the engine.

96civicdx2o3

Thanks a lot guys yea I ended up pulling the head earlier today and one of the exhaust valve has a nice little hole in it, and I have a question I pulled the head at tdc and some valves are open in cyl 2 and 3, are all the valves suppose to b closed? Is it bent valves ? I'm a post some pics up in a hour or so thanks

Deksinjo

It's OK, they just prepare for cycle. Inspect cylinder wall at burned valve , measure is head curve...

ek3turbo

usually when yu take the head off all valves shud be close just take it to a machinist to get it inspected and replace the valve seal and shave the head properly before you go back home and put it back together good luck

96civicdx2o3

Codes was p0302 p0304 p1399 p1300, I was loosing coolant and burning oil

96civicdx2o3

I ended up pulling a head off at the junkyard to buy but the valves were bent so I took some of the exhaust valves and put them in my old 1

96civicdx2o3

96civicdx2o3

Burnt valve ^

96civicdx2o3

Replacement valves

96civicdx2o3

No timing belt never broke it happened driving on freeway, just wondering what would cause the valves to burn?

Deksinjo

Damn man, you are really burned that valve , what about cylinder walls , what the are condition , are head curved ?

Deksinjo

P0302 cylinder #2 misfire
p0304 cylinder #4 misfire

p1399 random/multiple cylinder misfire
p1300 multiple cylinder misfire

To much full/overheat burn valve ... at same time missing ignition, full burn itself from engine exhaust heat ...

96civicdx2o3

I have to check 1 4 cyl walls, 2 3 seem good no deep groves or scratches just had some unburnt fuel on top of cyl 4, for the head I took a straight edge to it and it seems ok

96civicdx2o3

The codes was p0304 and 1399 after driving around I check it and there would be more codes 0301 0302 0303 0304 1399 1300 so I check which cyl was really mis. By pulling spark wires and only cyl 4 wasn't firing at all
Idk what's going on

96civicdx2o3

But I'm a put everything back on soon and take it from there

Deksinjo

Check all ignition, change spark plug lead, distributor cap/arm, spark plug ... you have problem with ignition, all cylinder have misfire

Mishako129

From my experience a cracked exhaust manifold is what caused the ex. valves to overheat and crack on my F22a1. There were not one but 2 cracks in the manifold, and there were 2 broken valves.

One in each cylinder.




Cracked manifold.

96civicdx2o3

Yea my exhaust manifold looks terrible, I think the preivous owner welded the cracks, really don't want to buy a new 1 since I have a 96 civic dx and the cat is connected to the exhaust manifold

96civicdx2o3

And I have swap dizzy from junkyard changed plugs and wires, cap and rotor, I kind of think the distributor I got from the junkyard is also bad ????

96civicdx2o3

Was looking at my headgasket a few min ago can this be the issue with the misfire

96civicdx2o3