Compression Check Specs

Natoe · Post by **Natoe** » Fri Mar 31, 2006 2:27 am

I am curious what a healthy EJ22T block should show on a compression check... i searched and searched and couldnt find numbers for what they should be.
Here is what mine looked like-bone stock in my impreza, a 1993 motor, no idea how many miles on it, but most likely lots.

1: 135 psi
2: 140 psi
3: 142 psi
4: 150 psi

Thanks for the help.

sammydafish · Post by **sammydafish** » Fri Mar 31, 2006 3:32 am

It's not so much a matter of how much pressure there is, but more the ballance. The pressure can change a lot depending on how you do the test. The proper way would be to pull all the plugs, disable the fuel system and do the test dry, then squirt some oil in the chambers and do it again wet.

You numbers are within 10% of each other. Although 135 is mildly low, I wouldn't be concerned, if you didn't disable the injectors is might have just gotten a little washed.

Natoe · Post by **Natoe** » Fri Mar 31, 2006 3:35 am

k thanks, yeah i figured they were all pretty close together which is what matters, except that 135. we just unplugged the coilpack and took each plug out one by one doing the test. (so there was still fuel goin in the cylinders)

Threshld1 · Post by **Threshld1** » Sat Apr 01, 2006 3:39 am

is pulling the injector connectors good enough or should the pump be disconnected and pressure relieved?

entirelyturbo · Post by **entirelyturbo** » Sat Apr 01, 2006 3:55 pm

Threshld1 wrote:is pulling the injector connectors good enough or should the pump be disconnected and pressure relieved?

Just disconnect the fuel pump, it's easier than disconnecting all 4 injectors.

vrg3 · Post by **vrg3** » Sat Apr 01, 2006 6:57 pm

Just pull the green SBF-2 fuse out from the underhood fuse box. Without SBF-2, you get no fuel and no spark because the ECU does not turn on.

Natoe · Post by **Natoe** » Sun Apr 02, 2006 2:08 am

haha yeah that sounds like the best way. next time.

Threshld1 · Post by **Threshld1** » Tue Apr 25, 2006 1:05 am

so a compression of:

#1 - 158 psi
#2 - 152 psi
#3 - 158 psi
#4 - 160 psi

on my 93 EJ22T im looking good?

Natoe · Post by **Natoe** » Tue Apr 25, 2006 3:23 am

looks pretty swell to me, better than my numbers

entirelyturbo · Post by **entirelyturbo** » Tue Apr 25, 2006 4:58 am

That's perfect. Your engine is as good as new.

93forestpearl · Post by **93forestpearl** » Tue Apr 25, 2006 6:48 am

I'm in the 140's at 185k abusive miles.

Not bad. Not bad at all

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Compression Check Specs

Compression Check Specs