I performed a leak down test on my evo ix today. I previously did a compression check on my engine and found cylinder 2 to be 18 psi lower than the other three. When doing a leakdown on cylinder 2 I heard air escaping from cylinder 3. From what I have read this could either be a cylinder wall crack or a leaky head gasket. The engine has got 132,000 miles on it. I am hoping its the lesser of the two evils. Is there anything else that could be causing it to leak out the adjacent cylinder?

 

Where are you hearing it from? From the exhaust or intake side? I'm guessing it's valves or head gasket. The valves aren't necessarily bent, could be carbon build up

 

If you are positive that you are hearing the air from the next cylinder i would remove the head. It needs to be removed to do the HG any way. Pull the head, inspect the block, new head gasket with new head studs. Tighten that thing right up. Gives you an excuse to do your timing belt and put some cams in if you don't have any yet.

 

The air was escaping out the adjacent cylinder #3 spark plug hole. My compression numbers were 90,72,90,90. With cylinder # 2 being the low cylinder. What really baffled me was that when I did a leakdown on #3 I thought I would hear air escape out of cylinder 2 but instead the air escaped out of the fourth cylinder spark plug hole. And made perfectly sure the test was done right.

 

What problems are you having with the car? Any overheating or anything. I have never heard of a 4g63 block cracking. ppl run crazy power on these. I wouldn't worry about the block

 

Ya in the back of my mind I knew there was a slim chance it was a crack on the block. It's most likely a head gasket due to the fact that all my compression numbers are low.

 

My car does not overheat nor does it have lack of power. What made me start investigating all this was that my car would have a hard time starting in the cold. When the temp. dropped here in Colorado to -8 below I could not get it started. So the problem gets worse the colder it gets. I replaced a few things leading up to this to help me narrow it down to low compression.

 

I wouldn't worry about it too much. Do everything or don't do anything. That is extremely cold. I doubt my car would start in that temp. It was 10 here and it took me 6 tries to start my car a few weeks ago.

 

Would you agree with me that with my compression numbers being as low as they are that the solution is most likely a head gasket? Also did anyone have anything to add on what I mentioned earlier about the air leaking out the fourth cylinder when testing #3

 

I've read on Honda forums several years ago that dropping a teaspoon of oil through the spark plug area does help with getting better compression tests. Pistons and rings haven't expanded enough to fill the small gaps. It's been a long time since I've done one of these compression tests. So I can't remember exactly what I've done. Sorry, I'm no help. You could google it if you're not confident of the process.

 

Unfortunately air leaking into the adjacent cylinder is a bad finding. How much air were you losing when you tested it? What was the pressure set at and what was it reading on your tester?

Your are most likely going to have to pull the head. I know that sucks. Was it pressurizing the radiator system at all?

 

I was using a Matco leakdown tester and I was getting about a 38% leakage reading when I tested cylinder #2. When I moved over to cylinder #3 I was getting a 100% loss. This made me think that I was not right at TDC on cylinder #3 but I checked three different times and every time I got the same reading.

 

There were also no bubbles seen in the coolant reservoir

 

Wow that's a lot of leakage, and it was all coming out the adjacent cylinder? 38% seems reasonable if it were a head gasket issue and air was only leaking out the adjacent cylinder. The sealing rings between cylinders isn't that big and can be blown out with a lean condition. No air escaping anywhere else? Valve cover, intake/exhaust valves, etc?

100% leakage on cylinder 3 seems wrong. Cylinders 1,3, and 4 should have been roughly equal in leakage going by the compression test. Something funny was going on there. Or at least as you stated cylinder 3 should have leaked back into 2.

 

You have to be on the compression stroke of the engine when doing a leak down test. Make you you're at TDC as well. 100% leakage and your car would almost not be running.