Compression Results, opinions please.

[BadMojo]

Here's a bit of background. I had my car at a Nissan dealer a while back and had them do a compression test just for the hell of it. The car was running fine.

Results (they never did tell me if they ever did a wet test):

#1 #2 #3 #4118 120 120 122

I didn't really trust these numbers, so I finally did the test myself today. Here's the problem. I relieved the fuel pressure and then foolishly put the fuse for the fuel pump back in (stupid, I know). So, with the injectors pumping fuel in to the combustion chamber...

#1 #2 #3 #4175 170 180 175

Everything looked good, but then I realized that the fuel pump was running...the smell of fuel was a subtle hint.

I pulled the fuse for the pump, cranked it a bit and then tried the test again. All of the cylinders looked good except for #2. That one came in at ~155 PSI. Tried it with a bit of oil and got ~175.

So, do I have bad ring in cylinder #2 or are the results of both my tests garbage?

I don't quite understand why all cylinders would be fairly close together until that last test. I plan to try again this week or possibly this weekend.

Any input would be greatly appreciated...I sooooo hope I don't have to get this engine rebuilt.

Thanks!

[NISTECH]

To be honest compression tests arent nearly as accurate as leak down tests. but If your doing the compression test. do it with the fuel cut as you did the second time, throttle to the floor,all plugs removed, crank so the engine lopes about 8 times each cyl. Do the test three times. take all three readings the 2 closest to each other are the most represntitive of that cyl's true compression. When doing the test three times you check all cyl's between each test. that way you lessen the chance of a poor seal of the tester itself.