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jon27405
Jul 24, 2008, 04:19 PM
I was the guy with the honda civic that wouldn't start. I did a compression test with both a wet and dry situation.

Dry:
Cylinder

1. 150 units of pressure
2. 140 units of pressure
3. 140 units of pressure
4. 55 units of pressure


After this I added some engine restore to each piston via the spark plug tube. After about 2 minutes, I conducted a wet test

1. 115 units of pressure
2. 170 units of pressure
3. 100 units of pressure
4. 180 units of pressure

These cylinders changed pressure so much that I really need an explanation on these. Please help

rhadsen
Jul 25, 2008, 06:20 AM
Looks like cylinder #4 has bad rings. How did the plug look in that cylinder? What made you decide to do a compression test - oil consumption?

Rob

jon27405
Jul 25, 2008, 07:56 AM
My plugs in cylinder 4 were burned completely black and smelled of gas. The plugs were absolutely brand new, I just took them out of the box. Lol. I was thinking that I seated a ring. But I was hoping that the oil I poured on top of it during the wet test would bring the ring back up. I will test the compression again today to see if the engine restore has worked its way down the cylinder walls and done its job.

TxGreaseMonkey
Jul 25, 2008, 08:11 AM
Classic ring problem on Cylinder #4. Most likely, you are facing a rebuild. Afterwards, use full-synthetic engine oil (e.g. Mobil 1 5W-30); then, it's unlikely you'll ever wear an engine out and have these problems again.

jon27405
Jul 25, 2008, 05:20 PM
I checked my compression again today, hoping that after a full 24hrs that the compression would improve but here are the results

1. 150
2. 185
3. 130
4. 210!!

These numbers are below the recommended compression and waaaayyyy about the varience margin the repair manual gives me. Would this keep a car from starting?