Just did a comp test. Drivers side bank came out as 11.2;11.5;11.2 Bar. Pretty consistent. Passenger side was 10.6; 10.6 10.8. Again pretty consistent.

 

The minimum value in the manual is 9.81 so all cylinders are within tolerance.

 

But why the differnce between each bank? And are these figures really acceptable or should I be looking at new rings/pistons?

 

Come to think of it shouldn't the turbo and non turbo have different compression figures. The manual only gives one.

I'm sure the manual gives 2 values if you look in the right place - it must do, the NA is higher compression.

 

How did you do the test and in which order ? Had you disabled the fuel pump and was the battery getting weaker when you were testing the lower pressure cylinders ?

I can only find one set of figures in the manual. It does not specify whether its turbo or non turbo. See pg EM9.

 

I disconnected the fuel relay, removed all the plugs. I forgot to disconnect the crank sensor. The procedure is in the manual on page EM9.

 

It is possible that the battery started running low as I did the passenger bank last. The order i took was cyl 1,3,5,2,4,6. But it sounded pretty well charged.

Hmmm, see what you mean, but the NA is 10.5:1 and the TT is 8.5:1 so the manual must have missed one. With a bit simple maths you can work out roughly what the pressure should be, if you know the volume of the combustion chamber.

Coogs, did you test with throttle open or closed?? This may also have a bearing.

 

RCD

 

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WOT as per the manual.