~~Need help, check out the bottom of this post~~

Finally I had a chance to do a compression check.


Little how-to:
You need:
-Compression Tester

-Spark plug remover

-only two sockets, one above for spark plugs, and one for coils

Your car needs to be hot. Drive it for 30mins and then stop and do a compression check. Wait maybe 10mins before removing spark plugs. It's a precaution for all engines with aluminum heads to not destroy the threads for spark plugs.
Step 1 - Remove the back seat cushion
Step 2 - Use a philipis screw driver to take off the cover of the fuel pump
Step 3 - Locate the power source for the fuel pump

Step 4 - Remove the plug, start the car and let it die

Step 5 - Disconnet the spark plug wires, and coils, disconnect the coils from the power source

Step 6 - Remove all spark plugs

Step 7 - Connect the tester to the cylinder 1

Step 8 - Crank the engine 5 times with 100% open throttle. (I forgot that last one)
Step 9 - Record all the readings
Step 10 - Repeat for all cylinders.


Here are my readings. Note that your readings might be different because I have 10.5:1 pistons and you don't .
Cylinder1:
First 60psi then 150psi

Cylinder2:
First 80psi then 180psi

Cylinder3:
First 90psi then 180psi

Cylinder4:
First 80psi then 160psi




I hope this will help a lot of people on this forum.
MODS if you want to make a copy to how-to section it would be great. I didn't want to start two threads.


~~NOW THE PROBLEM~~
After the compression check my engine is making this weird noise:
http://s19.yousendit.com/d.aspx?id=3...A0Q4J3VV8DZBFW
Can someone tell me if it is knocking (NOOOO) or not. WHY?

 

OH BTW, the hand that is holding the gauge is not MINE!!! It's my neighbor, I will buy him a nail clipper for Christmas.

 

Oh snap, I totally forgot about 100% throttle! WTF?
Do I need to repeat the whole process?


Also, my problem has been fixed. Always triple double check everything. I forgot to plug in one of the coils and two cylinders were not working.

 

Boe so what's the conclusion on our ticky valves?

 

What valves? Did my miss something?

 

bump

 

Just a quick addition: instead of going through the hassle of unplugging the fuel pump, you can just remove the crank angle sensor. It's the only sensor on the camshaft, driver's side. This will keep your injectors from firing.

 

yes you have to have the throttle open fully during the test for results to be accurate. It takes about 3-5 seconds worth of cranking on each cylinder to reach max compression output.

Also you want to ensure all other spark plugs are in place while testing the cylinder you're on. When you move to the next cylinder and remove it's plug put the other cylinder's plug back in.

If you did not do this on your test do the test again in the proper manner as noted above please.

If 180 psi was your max with the right testing then there is a problem. A leakdown tester will allow you to see if it's in the valves or if it's in the pistons.

 

if you don't have a leakdown tester then an older trick is to put about 2 capfulls of oil into the cylinder and redo the compression test. If the compression goes up significantly (15psi or more) then there is a ring issue. If it only jumps 5-10psi then it's most likely in the valves.

Another old school wat to check vavles is to loosen the racks for intake/exhaust rockers... then put about 80psi of air into the cylinder one by one. Now listen in the intake and the header for any leakby... if you hear it then you know that cylinders valves are bad. The cylinder should hold 80psi easily without any real leakdown occuring.