Compression Check

Sounds pretty simple, but theres some things i been reading up on. First off im doing this on a 95 240.. So i got this much so far unplug the wires from the sprak plugs, pull off the wires from the distributor. Now i have no center coil, i have like 2 connectors, so which ones do i disconnect? And do i remove the fues for fuel injection as well? And do i ground the wire i remove, i hear that if i dont, i may mess up the ignition or the ecu....

Sorry its bad quality, im too poor for a real camera, woo rock the camera phone....

http://i31.photobucket.com/albums/c358/Scope2x/Image005copy.jpg

if you have a factory service manual for your car it should tell you how to do it

i usually just pull the caps off the plugs, set em off to the side, pull the plugs out, insert tester into cylindar, crank for 2-3 seconds. But i dont know if that is the most accurate way to do it. I dont know why the ingnition being plugged in or not would matter, but i have been told your supposed to disable it?

dont forget your fuel injection, cuz while your cranking, it would be dumping fuel into your cyl.......

A tiny tiny bit of fuel, I think it would just all burn off when you start the engine.

Sounds pretty simple, but theres some things i been reading up on. First off im doing this on a 95 240.. So i got this much so far unplug the wires from the sprak plugs, pull off the wires from the distributor. Now i have no center coil, i have like 2 connectors, so which ones do i disconnect? And do i remove the fues for fuel injection as well? And do i ground the wire i remove, i hear that if i dont, i may mess up the ignition or the ecu....

disconnect both connections on the distributor. then disable the fuel injection. it can mess up the test and damage your engine. i did it on a fiends car a little while back i think the compression spec is about 120... not positive but i think. just make sure all cyl are close. and do it wet too to be safe

i think your making it more complicated than it really is.

1) Drive car to be warm
2) Open hood and remove spark plugs
3) If youve removed the plugs, then youve removed the caps off the top from distributer. You dont actually have to take anything off the distributer, just the caps out of cylindar
4) Put in compression tester with proper adapter/fitting, make sure its in good
5) hop in car, press down gas pedal to WOT (all the way) and crank the engine over
6) Check and record compression
7) repeat 1-6 for cylindars 2, 3 , and 4
8) Put everything back togethor, car should start fast with fuel in there

I dont ever disable the fuel system, my compression tester instructions dont even say you should.

alright. cool stuff man, thanks a lot.

i think your making it more complicated than it really is.

1) Drive car to be warm
2) Open hood and remove spark plugs
3) If youve removed the plugs, then youve removed the caps off the top from distributer. You dont actually have to take anything off the distributer, just the caps out of cylindar
4) Put in compression tester with proper adapter/fitting, make sure its in good
5) hop in car, press down gas pedal to WOT (all the way) and crank the engine over
6) Check and record compression
7) repeat 1-6 for cylindars 2, 3 , and 4
8) Put everything back togethor, car should start fast with fuel in there

I dont ever disable the fuel system, my compression tester instructions dont even say you should.

That's how they do it at my garage.

mabye you should sticky the the compression test procedure if you can so people dont have to repost...

^
Sounds good

theres another thing, if your going to use an adapter, make sure you have a way to get the adapter out if it gets stuck in there. I had that happen, and couldnt get a socket around it so i had to push a flat blade down into the middle of the adapter, and twist it out once i had the screwdriver in the adapter. At first i was like "fuck, now im going to be taking off a head" lol