toddk911

can you use a compressor and the same type of connector to do a leak down?

Duke

What do you do about the fuel, simply remove the DME-relay?

David Floyd

This will give you some info,

http://www.geocities.com/dsmgrrrl/FAQs/leakdown.htm

Peckster

To a point, consistent readings between cylinders is more important than high numbers. Less than 5 psi, you're laughing. Mine's been at 135 for all four for years and it runs great. I'm sure the accuracy of cheap gauges varies widely,

johne

todd,
the throttle being closed caused about a 10 percent low reading, thus explaining your low readings. That is what we found on my buddies miata anyways.

Regards,
John

toddk911

cool, John. Thanks for the info!!

toddk911

YOU ALL WON'T BELIEVE THIS ****!!

I was doing the test again, this time with full throttle, and the screw in part came off from the hose and it is now stuck screwed into the spark plug.

can't get a socket on it and too narrow to get pliers on it.

HELP???

Steve Lavigne

Had the exact same thing happen to me with the POS Sears compression tester. I can't remember how I got it out of there, but I do remember that I took that piece of junk back. I found the nearest Snap On truck and bought the *last* compression tester I will ever buy!

EDIT: I pounded 6mm 1/4" socket over the end of the fitting and then was able to unscrew it with a ratchet. See this thread.

Jfrahm

So do you think the readings would be higher if the AFM was pinned open as well? It does sort of close like a throttle, but the volume of air behind it is so large it may not matter (unlike the throttle plate, which has less air behind it, just what's in the intake plenum.)

-Joel.

toddk911

Thanks Steve.

What psi do you use for leak down??

Also, for the leak down do you need the guage, or can you do a rough test and just inject air, and listen for leaks??