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sliEighty
05-22-2007, 08:05 PM
my motor cranks but doesnt turn over. im trying to run a compression test what should the compression be on a cold sr
johngriff
05-22-2007, 08:07 PM
145 psi should be the minimum.

Do the test w/ the throttle body OPEN, and pull the fuel pump fuse out.

Bonus.
sliEighty
05-22-2007, 08:09 PM
alright sounds good thanks a bunch
GSXRJJordan
05-22-2007, 08:30 PM
yeah, pull the fuel pump fuse (not just the igniter), and crank it 7 or 8 times with the throttle all the way open. That's the trick ~ and 145 would be a great number to see cold, but realistically 130+ on an 'off the container' engine can still pull 150+ with a couple drops of oil in there.
statik
05-22-2007, 09:17 PM
Just pull the CAS plug, no cas signal injectors and coils won't fire, remove all plugs, WOT
steve shadows
05-23-2007, 11:55 AM
145 psi should be the minimum.

Do the test w/ the throttle body OPEN, and pull the fuel pump fuse out.

Bonus.

actually 130 is acceptable as long as all cylinders are within about 5-6 psi of each other.

Ive seen sr's read this low and run great and seal fine, sometimes cold and hot readings can vary (as well as motors that have sat for a long period without oil pressure or vapor of any kind to pressurize the c-case).
TheWolf
05-23-2007, 12:36 PM
A leak down test with a mechanics stethiscope is usually more usefull. Test gauges have variation. It's more to be used as a comparitor with the others.
sliEighty
06-05-2007, 07:18 PM
ok so i did the test the 1st and 4th cylinder are both around 155 and the 2nd and 3rd are around 140. the story of the car is that it overheated and when i went to pull the coil packs they were all melted i pulled them the plugs smelled of gas so i thought maybe the coilpacks failing would have saved the hg. so i ordered new coilpacks they should be here soon... but now im thinking a new hg would have been good to buy also now with these numbers... maybe its just me thats messing up im not to sure
MyLevinGTZ
06-05-2007, 09:59 PM
those numbers aren't too bad. it should run that way but if your coilpacks were melted, it's possible your ignitor chip could be fried as well if the wires in the coilpacks mayhave been crossed.