Compression

[265bhp gtir]

That what i did yesterday and put a drop of oil in the bores and it made 95psi on all 4

 

[pulsarboby]

with oil down the bores, your psi would have gone up to at least 15
this would indicate that either your valves are letting by big time or your compression testers fcuked.
oil will raise the psi if you have worn pistons and rings, so you can scrub them out as fine, which in a way is good news!

 

[MarkTurbo]

oil will raise the psi if you have worn pistons and rings, so you can scrub them out as fine, which in a way is good news!

Isnt that what happened? He put oil in the bores which gave a higher reading? If thats the case then its the rings ;-)

 

[pulsarboby]

Isnt that what happened? He put oil in the bores which gave a higher reading? If thats the case then its the rings ;-)

my mistake, didnt look to see what psi was in first post which was 68psi so has gone up with oil:doh: yes marks right it is fcuked rings, my appologies for being a dombat:der:

 

[R called Jay]

I'd try another compression tester begore getting too involved tbh.

 

[sumo]

am with r called jay get a uther tester or get some one to do it for u if ur car runs fine then the next day it dont it could be a sensor like take out the o2 sensor and clean it with brake cleaner

 

[265bhp gtir]

it just feels a bit down on power sometimes iv tested it twice and tested the compression with another tester they both give the same reading within a few psi

 

[KF79GTIR]

warm the engine pull the dip stick out and rev the engine if you see smoke pour out the hole then your rings or pistons are worn is it running lumpy at all miss fireing or any thing else

 

[265bhp gtir]

it dose run a bit lumpy sum times its like its missing very slightly iv put new plugs in it but its just the same

 

[oap-r]

it dose run a dit lumpy sum times its like its missing very slightly iv put new plugs in it but its just the same

If your compression is that low,it's no wonder it's missing.it must be struggling to ignite what little mixture you've got in the cylinders and there must be oil vapour in there as well.

 

[KF79GTIR]

have you had any more probs yet have found out the problem

 

[265bhp gtir]

Well the car still is the same realy some times it feals a bit slow and other times it fine.one of them new focus st turbos tried racing me the other nite and i just left him when the turbo came in so there carnt be much wrong with it. The compression is still the same and after that wind yesterday i now have a big dint in my n/s/r quarter

 

[Fast Guy]

Did you have the throttle open when you did the compression test?

 

[265bhp gtir]

Did you have the throttle open when you did the compression test?

Yes i did have it open. I went down to dp motorsport at the weekend and he sed i should check the cam timeing as its not smoking or loseing oil. I think i will try another comp tester before i do that