Compression test results (opinions please)

[J.C 10]

Hi

I've just carried out a compression test,

I thought I did it properly but then read up that you should remove the intake from the MAF and put you foot on the accelerator, but apart from that I think the results are pretty accurate

here are the results

 

CYLINDER, 1....2....3....4....5....6

1st try ...185 190 170 183 170 190

see note below

2nd try ..190 198 178 190 180 194

 

Note: I was a bit worried about the results for 3&5 so I concentrated on getting the best from them(making sure tester had good seal ), then I re tested the remaining cylinder,

 

 

what are peoples opinions?,

do they look ok?,

am I right to be a bit worried about 3&5,

is it possible the head gasket is leaking between 3&5.

All spark plugs have the same discolouration(light grey/brown) which I understand to be OK, I've taken photos of the plugs if people will think it'll help.

 

the engine runs well but has a vibration from idle to around 2000rpm(worse between 1500-2000), I have a Mk3 Golf VR6(OBD2) and it's a lot smoother than this one.

 

I look forward to you replies

Steve

Edited April 30, 2013 by J.C

[Supercharged 2]

All well within tolerances... plugs looked ok I assume?

 

Also you really do need to have the throttle wide open and also have the engine warm with the fuel pump or ECU relay / injector wiring loom pulled...

[J.C 10]

All well within tolerances... plugs looked ok I assume?

 

Also you really do need to have the throttle wide open and also have the engine warm with the fuel pump or ECU relay / injector wiring loom pulled...

Thanks for the reply

Yeah, plugs look good,

engine was warm,

fuel pump fuse removed and plug pulled off coilpack

[Kevin Bacon 5]

Fairly common those readings. You don't get many VR6s with 190+ across all 6. As Supercharged said, the lower readings are within tolerance. 160 or lower then I'd be concerned!

[KipVR 1]

The 2.9's were never as smooth at idle as the 2.8 anyway, as the others have said the results seem ok, if you really wanted to be sure you could do a leak down test.

[J.C 10]

Thanks Kevin, Kip and Supercharged,

I'm not too concerned about the idle, I'm more worried about the vibration up to 2000rpm,

It had a new clutch fitted before I bought it and I found one of the bolts (one next to the earth strap) completely loose and a hose clamp on the oil breather loose, therefore leaking oil into sparkplug 1 area,

Also there is thrust release bearing squeal(actually more like a faint squeak).

to sum it up, I've started to doubt the integrity of the clutch job( maybe they forgot to tighten the clutch bolts!!!) and am thinking it might be a good idea to remove the gearbox to check everything.

Maybe someone can give it a once over at Stanford hall on Sunday

I'll look into giving it a leak down test