MardiGrasMax

iTrader: (14)

Ok so my 98 Max has 18k on it now, and I use the juice and I'm on vacation!! Sooo lets do a compression test to check that motor out.

Since I'm cheep and havent bought a shop manual yet, I need some one to please tell me what the procedure is to do this correctly, disconnect the fuel system (how?), etc etc etc? and what the factory tolerances are.

THANKS!!

Keven97SE

Straight from Page EM-10 of the Factory Service Manual (for 1996 Maxima):

"
Measurement of Compression Pressure

1 Warm up engine
2 Turn ignition switch off
3 Release fuel pressure (remove fuel pump fuse and crank engine a few times)
4 Disconnect ignition coils
5 Remove all spark plugs
6 Disconnect all injector harness connectors
7 Attach a compression tester to Cyl 1
8 Depress accelerator pedal fully to keep throttle wide open (or rig at throttle body)
9 Crank engine and record highest gauge indication
10 Repeat for every other cylinder
11 If compression in one or more cylinders is low, pour a small amount of engine oil into the cylinders through the spark plug holes and re-test.

Notes:
- If adding oil increases compression, piston rings may be worn or damaged. If so, replace piston rings after checking piston.
- If pressure stays low, a valve may be sticking or seating improperly. Inspect and repair valve and valve seat. If valve or valve seat is damaged excessively, replace them.
- If compression stays low in two cylinders that are next to each other:
a) The cylinder head gasket may be leaking, or
b) Both cylinders may have valve component damage. Inspect and repair as necessary.

Standard 185 psi @ 300 rpm
Minimum 142 psi @ 300 rpm
Difference between cylinders 14 psi @ 300 rpm

Use a compression tester whose rubber end is less than 20mm in diameter. Otherwise, it may be caught by the cylinder head during removal.
"

MardiGrasMax

iTrader: (14)

Thanks Keven!!!

MardiGrasMax

iTrader: (14)

5 cylinders at 210psi one at 207.

If 185 is standard the 210 is like new?

Wow, Mobile 1 really works! Even on the juice!!!

Nismo87SE

Have you ran a compression test since going with boost?

MDeezy

iTrader: (27)

damn 210 is good.

vortechpower

iTrader: (1)

Did you mean 18,000 or 118,000. Wow I need to do a compression check.

goodhead

iTrader: (4)

could your compression ratio be higher because of the setup??? thats what it looks like

HarrisH

iTrader: (1)

LOL A high compression means most of the time means you have carbon buildup.

gtr_rider

iTrader: (50)

You all are morons, look at the posting dates

goodhead

iTrader: (4)

LMAO

Sprint

iTrader: (10)

HarrisH

iTrader: (1)

hahaa

Bags

iTrader: (3)

Thanks luke.. and we are done here