ok on both rotors I got 60psi if I left the valve closed, with the valve open I saw about 45-50psi.

this is a s5 n/a motor, pulls pretty strong, dyno'd 165 whp about 6 months ago and it "feels" just as strong.

It also starts pretty easy, It'll flood sometimes, but its also on a s4 ecu+ extra fuel for starting.

so whats up with this?

 

is your battery fully charged?

do you have it at WOT? read kevin landers' writeup on his site

 

no it was not at wot
the battery was charged.

how much of a difference can wot make?

 

Do it again and you'll see

Also, was this taken while warm? and from which plug hole?

 

yes warm engine and leading hole

 

ALWAYS take it at WOT.


...and of course, remove the EGI fuse. But I am sure you knew this.

Anyhow, compression tests are evil. If it starts fine cold or hot, all is fine.


Spec.

 

Compression is supposed to be taken through the trailing as per FSM.

 

Throttle must be propped fully open.
BOTH trailing spark plugs must be removed - Mazda spec uses trailing.
If you're going to insist on leading, then the readings will be slightly lower.


-Ted

 

so you need to do this using the trailing plug holes? but you leave the leading plugs in the motor right?

 

yes, only remove the trailings

 

How many miles are on the engine?

 

And disconnect the CAS, it's never good getting zapped when messing around with your car.

 

but that takes all the fun out of working on a car

especially if you have a friend that doesn't know better

 

I was diagnosing an obd1 integra for a dead cylinder when I leaned over the engine bay and my arm brushed the cold air intake on it, next thing I knew I was picking my *** up off the floor The intake had rubbed a hole in #1 plug wire shorting it out. Those things have a hell of a coil in them.

 

I was checking for spark on my old 93 escort, put a screwdriver into the wire and grounded it out on the valve cover, asked my mom to roll the car over


I threw that screwdriver 20 feet up into the air