Ok, so the fiesta has sat for over a year waiting for attention, and by now im sure that it could use a prelubing and such. Over time don't the rings lose seal too though?

On other cars, ive been advised to run the car like i was seating rings (2nd gear deceleration, coasting down hills, varying speed etc.) after letting them sit that long. And its been great advice. Cars that smoked initially run like champs after a few miles. But im not trying to drive around, its got no interior at all atm. I just want to see if the cylinders are any good.

So, do i start it up and let it warm up before i test or do i just do a cold test and hope for consistent-ish results? I mean it might not even fire up so this may be a moot point, but it WAS running( poorly) when it got parked.

 

A cold test willuch cylinder and ring wear you have. Which is kind of what the test is for. Once you run it, you can retest to see how much compression you restore with the ring seating procedure. On cylinders that test low, add one tablespoon of oil through the spark plug hole and retest. If compression increases, the rings are leaking. If compression does not increase, you have a leaking valve. A cylinder leakage test will determine what valves are leaking and also how well the rings are sealing.

 

so theres no reason to warm up the car to get the rings coated with oil before I do the initial test? import guys are telling me a cold test is "worthless" i dont really agree but some of their reasoning is understandable

 

the main being that a cold test on an engine run yesterday and a cold test on an engine run eight months ago are two different things.

 

My point is, perform both. This will show you how badly worn your rings are. A car with new cylinders and rings can sit for several months and still test within 25% of spec. If your car tests significantly lower than this, you know that you have worn rings. It may still come up to spec with oil in the rings but at least you know.