Thread: Toyota Tercel Compression

1991 Tercel, compression test shows 0/cyl 1, 0/cyl 2, 30/cyl 3, 180/cyl 4
Timing belt is ok and is in time.
Where do I start??
Tim

The next thing to do is do a little better inspection of your timing marks VS your actual machanical timing, you say the marks are lined up, is #1 piston actually lined up at TDC and both the Intake & Exhaust valves are closed.

The next thing to do is a wet compression test, put a little engine oil in the spark plug holes to try to seal the surface of the piston rings to the cylinder walls. Put your oil in all the cylinders then motor it over for several rotations to blow excess oil out prior to screwing your compression gauge in. You may want to lay some rags over the spark plug holes to catch the excess oil so it doesnt get sprayed all over your motor or the underside of your hood.

If compression comes up to normal range, reinsert plugs and try to start the engine again. Post your findings please. Also be sure your relief valve is not leaking on your gauge and do a good six rotations of the engine per cylinder compression test.

It sounds like a head gasket Put your plugs back in and see if it makes a difference