DIY Compression Testing your engine

This is a very easy way to check the health of your engine.


First this applies to all cars pretty much... Hondas are just so easy to work on this seems much easier on them!

*You will need to rent a compression tester from a local car store or buy one
*Sprak plug socket
*Easier with a friend but not necessary

Here is your starting point.
http://i918.photobucket.com/albums/a...t/100_5741.jpg

First thing is you need to remove the four 10mm bolts holding the spark plug cover on

http://i918.photobucket.com/albums/a...t/100_5742.jpg

Next we'll remove the four 10mm bolts holding down the ignition coils. You will need a 10mm deep socket for that. Then lift the coils and unplug the blue connectors

http://i918.photobucket.com/albums/a...t/100_5743.jpg

Now remove its time to remove the spark plugs. I hate the oring spark plug sockets I recommend buying the magnetic sockets!

http://i918.photobucket.com/albums/a...t/100_5746.jpg

Now keep your plugs in order and compare them... right away I know I'm in trouble as the 3rd cylinder spark plug has liquid on it.... :noes:

http://i918.photobucket.com/albums/a...t/100_5747.jpg

Now you must do one of two things. Depending on the car, you can either pull the fuse for the fuel pump or you can do as I did and pull the injector clips off. Either way you don't want fuel dumping into the engine while testing!

http://i918.photobucket.com/albums/a...t/100_5748.jpg


I don't attach the gauge yet on the tester because it's easier to instal in the cylinder without. But start with cylinder 1. (closest to timing chain/belt) You don't have to start here but I recommend it.

http://i918.photobucket.com/albums/a...t/100_5749.jpg

Now attach the gauge and head into the car.

two thing you need to remember!

a) hold the gas to the floor. You want to test the compression at WOT (wide open throttle)
b) you must be repetitive and bump the engine the same each time for every cylinder!

So hold the gas and crank the engine of 3-5 times. I always do four. However many times you do it just make sure they are all the same! Now go look at your gauge

So here are my cylinders in order

#1
http://i918.photobucket.com/albums/a...t/100_5752.jpg

#2
http://i918.photobucket.com/albums/a...t/100_5753.jpg

#3
http://i918.photobucket.com/albums/a...t/100_5755.jpg

#4
http://i918.photobucket.com/albums/a...t/100_5756.jpg



To my surprise I have not one but two screwed cylinders. You want your cylinders to all be consistent and within a small amount of eachother. As my first two cylinders are.
Compression Pressure:
Above 930 kPa (9.5 kgf/cm , 135 psi)
MaximumVariation:
Within 200 kPa (2.0 kgf/cm , 28 psi)

If you want to test for a ring you can do a wet test now and pour a little oil in the cylinder and test again to see if the compression bumps up.


I hope your engine results don't turn out like mine!!