Help with a compression test, please

I'm new to doing compression test, so here is what I've done so far. I warmed my car up, disconnected the coil pack wires, put a block on the throttle to hold it open - and then performed a dry test, then a wet test. These were my results:

Port 1: 80psi dry and 80psi wet
Port 2: 80psi dry and 100psi wet
Port 3: 75psi dry and 80psi wet
Port 4: 75psi dry and 98psi wet

Can anyone let me know if these results are any good for a car of my age and mileage (89,700)? It had the air filter and timing belt changed at 55,000 miles. If you think the results are that good, please state why and what could be the problem.

Oh, and the car had not moved for three-four years before I bought it three months ago.

Asked on 13 December 2012 by christof2009

Answered by Alan Ross
Well the figures that you have produced sound extremely low, a 1.3 Fiesta engine should have around 13 to 16 BAR (188-232psi). Are you sure of your figures, and if they are correct then it would indicate internal wear.

Given the figures you may want to check the valve clearances to make sure they are correct and then re check. Did you make sure that the engine was warm and that it was turned over enough to register the highest reading.

If the figures are correct then it would indicate that the cylinder bores are worn/the piston rings are worn.Or that the head may be warped.

You may want to go to:

www.gregsengine.com/cylinder-compression-testing.h...l

As this may assist with your checks...
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