High compression readings

lewis

New Member
Hello guys

First of all I am new to this website so I'm not expecting help straight away from everyone.

Just done a compression test on a non runnner that I bought and I got 15 bar on all 4 cylinders.
I know that this is higher than expected but is it a problem?

Many thanks,

Lewis
 

bensmith907

New Member
Wow 220 psi. Are you sure its a gtir engine as the sr20det engine differs between car types not sure if compression figures are one of those differences!
 

bensmith907

New Member
Beyond me I'm afraid. Are you sure your gauge is reading in bar and reading correct? I think there are higher compression pistons available to fit in but not sure what you would expect from them! Hopefuly someone else will clear this up for you soon
 

lewis

New Member
It's going in to Bob at GTiRus sometime soon to have a look and getting it running. I basically bought the car as a non runner that was only firing on 2 cylinders.
By the looks of things after the compression check being equal on all cylinders (probably was the gauge playing up) I am confident that the internals are fine.
Under the bonnet, the wiring for the injectors is a complete mess with all the plugs missing and basically a home made attempt of connecting the wires in place. You never know, it could be something to do with that. The car was originally running big spec before I got it and he simply tried putting it back to standard and gave up basically. I was told what needed doing to get it running again and he was true to his word so far. (He did mention the misfire)
I did have a forged Sunny before hand which was 12 bar maximum, so I was quite shocked to see these high readings to say the least!
 

Fusion Ed

Active Member
Will be your gauge I'm sure.

If its all been played with make sure you get it computer on it to make sure that everything is reading how it should be.
 
P

pulsarboby

Guest
ive seen this before on 2 occasions with readings in excess of 200psi coupled with oily/smokey engines (its quite unusual though and can be misleading)

on a stripdown it turned out the rings were seized on the pistons and the piston crowns were heavily coated in carbon/oil this obviously creates a temporary good seal with oil bypassing the oil control rings on compression testing (similar to doing a wet compression test) ie putting a spoonfull of oil down the plug holes which temporarily makes a perfect seal round top of piston, this determines whether theres wear to piston/cylinders or valve leakage.

i hope in your case that im wrong and you have a faulty compression tester but i somehow doubt it tbh
 
I've had this on a used engine I bought and was down to one of the cams being timed a tooth out.

Reset the timing and was back to normal.
 
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