compression on a 3b

[denniselbows]

evening all over the weekend i finally managed to have a quick look at my car as it has been using alot more fuel than normal so wile i was inspecting the spark plugs i did a quick compression test on the cylinders. this is what i got on a cold engine and starter cranking.
number 1 130 psi
number 2 130 psi
number 3 120 psi
number 4 115 psi
number 5 115 psi

what would the average presure expected to be. i can see they are not all equal but am unsure what i should of seen.
your thoughts please.

dennis

[AndyP]

See here:-

http://www.s2forum.com/forum/showthread.php?t=16800

7 bar is 101.5psi, and a 3bar difference is 43.5psi so your figures are not too bad, and if you check them again when warm you'll probably find they are much closer to spec.

[denniselbows]

thanks for that link andy i did a quick serch under compression before i posted but didn't come up with that one. when i did my test i only pulled the ht lead off the coil so fuel was this giong in do you think the bores may of got washed a bit and that could be why the pressure drops as you go down the cylinders?

[AndyP]

Could have done, try getting it up to temp, then pull the fuel pump fuse which will depressurise the fuel system, or unplug the injectors. Take out all the plugs and prop the throttle fully open.