I have been seeing alot of questions about compression and how to test, so here is a writeup i did.
Compression Test by Smaay
1. Open hood
2. Remove engine plastics with 5mm Allen Wrench.
3. Plastics removed
4. Reach behind engine to unplug power steering sensor
5. Remove the four 10mm bolts holding coils.
6. Unplug coils
7. Remove the two 10mm nuts holding wiring harness.
8. Lift wiring harness out of the way.
9. Pull all four coils.
Coils removed exposing sparkplugs
9.5 unplug the 4 injectors so they dont squirt.
10. Using 5/8 spark plug socket and suitable extension (6-8 in.) remove and inspect sparkplugs. They should be a copper color like pictured.
Image of compression tester purchased at Autozone/Pep Boys/Kragen/Napa/etc.
11. Screw compression tester into cylinder 1 hand tight.
12. Hold down gas and clutch at the same time, crank engine over about 6 times, until needle stops jumping on compression tester
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13. Record results.
14. Release air pressure from tester and repeat for each cylinder.
Straight from the Toyota Manual (BGB)
1ZZ-FE 1,500 kPa (15.3 kgf/cm2, 218 psi)
2ZZ-GE 1,400 kPa (14.3 kgf/cm2, 203 psi) or more
1ZZ-FE 1,000 kPa (10.2 kgf/cm2, 145 psi)
2ZZ-GE 1,000 kPa (10.2 kgf/cm2, 145 psi)
Difference between each cylinder:
1ZZ-FE 100 kPa (1.0 kgf/cm2, 15 psi) or less
2ZZ-GE 110 kPa (1.1 kgf/cm2, 16 psi) or less
15. After test complete, put car back together in reverse order.
16. DONE! Have a beer to celebrate good results, or sulk in sorrows.
edit: this will throw a CEL for misfires. there is a fuse you can pull to prevent it but im not sure which one it is. but just unhook your negative terminal on the battery for 5 minutes and it will reset the CEL. Also the car might have a hard time starting, dont worry, just give it a few more cranks. It will start