I just purchased a 944 that has been sitting for four years. The car has 93K miles on it, compression check shows 175-180 psi for three cylinders and 120 for one. Squirted oil in low one and it did not change, any ideas? The reason I ask here is the 944 bird board is not real active. If you want to know how good this board is, go elsewhere! You can PM me if you don't want to clog up the board, I have other questions to.

Randy

Randy, if the car sat for 4 years, you could have stuck rings on that low cylinder. You can try an oil change and putting some miles on it and see if it changes anything.

You can pressurize the cylinder with air, with both valves closed and see/hear where it's losing pressure. If it is valves, it'll leak at the intake or exhaust. If it bad rings/cylinder, it will leak into the crankcase.

Good luck
Ed

I agree with Ed,

It is common to see this on a 944, number three cylinder is the one that I have seen have low comp most of the time, but Ed is right, do an oil change and fire it up for 20-30 minutes and vary the rpms (driving or not) then recheck With 944's (you did not mention what year). Also applying some air via a leakdown tester can at least find the source of your problem, most likely with the addition of oil and no changen you have a valve seating problem, or bent valve problem on that cylinder, If you live(don't remember from your post) near me (Boston) you can borrow my leakdown tester. You will need compressed air.

Three things are most probable to happen beside the low compression. The timing belt will need to be done at 93K, the pan gasket will leak, and make sure you cut open the oil filter and look for rod bearing material inside. The crank on these is very hard, and if you catch the number two rod bearing early (this is the one that is oiled poorly) many times the crank can be polished and reused and a new bearing installed. You will need the belt tensioning tool for the balance belts and the timing belt, but some shops will allow you to rent it for the weekend. If it whines it is too tight, if too loose, when the engine first starts up it may skip a tooth and damage the motor. I am assuming you have an 8 valve 2.5 liter. The 16 Valve is another story. As for the water pump, I have always changed them while doing a timing belt. But some disagree (DEMS) (just kidding)

But the best thing I have ever seen used in a 944 was this overflow bottle anode available from performance products. It is the sacrificial lamb for the cooling system. I beleive in them so much, that every water cooled car I own has one. It reduces electrolysis in the cooling system. And it really works.

Other minor things to watch out for depending on the year. Early cars 83-85.5 make sure the windshield seal and area under the battery is in good shape and the DME in the right hand kick panel in front of the door does not show water stains on it, if it does, open it up clean it and apply a light coat of WD 40 to prevent corrosion, I said Light. Front ball joints in the later cars are notorious for going bad, If the control arms (front) are aluminum it's a later car, if they are steel, don't buy the Porsche ball joint, go to the VW dealer and get a Rabbit ball joint, same thing less ChaChing. And if it has 15X7 Fuchs on the front, call me, you need different wheels and tires anyway, and I need those for my race car.

Hope this helps,

If you want a parts car, I have an 87 for 1200 bucks that needs a clutch, Pickup Boston only.


Erik Madsen E prod 914 NESCCA

Erik is right on the money. The only other thing I would add is make sure your tensioner rollers have been replaced with the updated ones. You did not indicate which cylinder had the low compression, I'd wager a pint of Guiness that it's the #3 cylinder. Pull the plugs and the fuel pump relay, squirt some Marvel Mystery Oil into each cylinder and crank it over for a few seconds. Put the plugs and relay back in and drive the bejesus out of it for half an hour or so. Then check your compression. I've got a lot of "hood" time with the 944's so feel free to drop me a note. Your right the bird list is fairly light on the 944 stuff, the Rennlist board is much more active.

My best,
Mike D.