How do you do a compression test on a Subaru?
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- Pull ignition fuse. – Fuse remover is located next to battery:
- Connect compression tester into each cylinder:
- Now it’s time to crank the engine with FULL wide open throttle. Crank the engine 6 times.
- Repeat the test for each cylinder and pray numbers come out good: :banana: 02 WRX – Tuned by Junior 301whp.
How do you do a compression test on a boxer engine?
To check compression, all the spark plugs are removed. The ignition coil is then disabled or the high-tension lead is grounded. The throttle is also held open. The engine is then cranked for a few seconds using a remote starter switch or a helper while a compression gauge is held in a spark plug hole.
What should the compression be in a Subaru?
As a rule, Subaru engines should have 142 to 170 lbs. of cranking compression with no more than 10% difference between any of the cylinders. Low compression in one cylinder usually indicates a bad exhaust valve.
Where can I get a compression tester for my Subaru?
The tester was only $17.99 at Harbor Freight with hose, and fittings for multiple spark plugs. It worked fine. Cylinder 2 is low, is this OK, or maybe a problem with the valves ?
What are the results of the compression test?
Here are the Compression Test results. and disabled fuel pump before the test. The tester was only $17.99 at Harbor Freight with hose, and fittings for multiple spark plugs. It worked fine. Cylinder 2 is low, is this OK, or maybe a problem with the valves ?
What should I do if my compression test is low?
If compression is low in one or more cylinders, you can isolate the problem to the valves or rings by squirting a little 30 weight motor oil into the cylinder through the spark plug hole and repeating the compression test. The oil temporarily seals the rings.
As a rule, Subaru engines should have 142 to 170 lbs. of cranking compression with no more than 10% difference between any of the cylinders. Low compression in one cylinder usually indicates a bad exhaust valve.
The tester was only $17.99 at Harbor Freight with hose, and fittings for multiple spark plugs. It worked fine. Cylinder 2 is low, is this OK, or maybe a problem with the valves ?
Here are the Compression Test results. and disabled fuel pump before the test. The tester was only $17.99 at Harbor Freight with hose, and fittings for multiple spark plugs. It worked fine. Cylinder 2 is low, is this OK, or maybe a problem with the valves ?
If compression is low in one or more cylinders, you can isolate the problem to the valves or rings by squirting a little 30 weight motor oil into the cylinder through the spark plug hole and repeating the compression test. The oil temporarily seals the rings.