compression test
 

Ok, I have the intercooler piping/elbow out. I removed the top two sprak pulg wires. Then I reached in and felt the plugs and wondered...what tool do I use to take these off? Any help appreciated

I am doing a compression test....
I am figuring i remove the top 2 plugs and then stick in the compression tester to where the plugs went and crank over engine...is this how it goes?

I cant start my engine but it is still getting air/fuel/spark...so is it still possible to test compression on just having it turn over as much as it can?

Do I need to remove any fuses while turning th engine over?

Thanks for the help guys...always appreciated! =)
Hope results come out good

if you want to know your motor condition without going through all that, you can just check your boost guage.

During idle, your vacuum should be hitting above 450mm/cm^2. If below, most very likely you will be needing motor rebuilt due to low compression.;)

there is a bunch of procedures to do. There should be a few threads about this.

off the top of my head......

unplug ONE spark plug at a time and use the top one.
take fuel/spark fuse out
press pedal all the way down
take check valve out of compression guage

watch for 3 even bounces

when cold the readings are inaccurate

WTF is 450 mm/cm^2 ??? those are some crazy units, man ;) . If your vacuum is less than 450 mmHg that doesn't mean that you'll need a rebuild soon... My compression is 7.2 for both rotors for all faces and my vacuum on a great day 430 mmHg (usually 410 or 420). It's a stock motor with over 60k on it, so it's a little tired, but it runs hard and will not need to be rebuilt soon. My point is, you can't tell that you need a rebuild from a vacuum reading. As far as your compression check... take it to the dealer or someone who has the appropriatre electronic equipment to read it accurately.

With a street port idle vac will go down.

I think there are too many variables to just check vac at idle.

compression checks are not that hard. I don't think it's worth 70 bucks or whatever to have the dealer tell me my car is fine.

As long as its running dont worry about it. You can pull one leading plug out and a time and pull the main efi fuse then just turn the engine over. Listed for all even bounces.

STEPHEN

compression is 5.2 kg/cm^2 on rear rotor and 12.5 kg/cm^2 on front rotor. Also equals 70 PSI on rear rotor and 185 PSI on front rotor. Looks like i am getting a rebuild.

Your numbers are not possible, at least on the front rotor. Maximum psi is about 125 psi for a new motor. The difference between rotors looks bad though.

Using the right tool?
 

Rotaries require a special compression gauge. If you're using a piston gauge, it might explain the numbers you are getting.

Beast

probably..but it atleast showed me what I needed to know. All for plugs were pulled and both readings on front rotor and back rotor were the same. But the rear rotor had only about 1/2 the reading of the front rotor BOTH times so I know I need rebuild....but thanks for letting me know about the #'s

a piston guage will work fine.

you just have to take the check valve out.

Lots of ppl use them.

when you have a suspicion that your motor is blown you dont need a guage to tell you anything. Just pull the fuel pump relay take out 1 of either plugs on each housing out and listen. Do one plug at a time then replace it and go on to the next housing. youll hear a pattern of the motor spinning over it needs to sound the same on all 3 beats or there is a problem

now to do a relative compression test to see what the condition of an old motor is a guage is needed

sorry about your motor