94ford5liter

I did a compression test on my 94 gt because it has been running bad and got the following results:

1 - 135
2 - 136
3 - 141
4 - 145
5 - 150
6 - 150
7 - 154
8 - 153

I thought the readings on #1 and 2 seemed kind of low and it doesn't seem like a coincidence that they are right next to each other. When I start the car it makes a prominent ticking noise, idles high for a little bit, and the motor vibrates then smooths out. It also sounds like an exhaust valve(s) is stuck open for a minute.

I'm wondering if it is a bad head gasket, valve not sealing right, or bad lifters. A head gasket seems unlikely to me because I just put rebuilt heads on it with good head gaskets. After warming up, the car runs like it has a miss and a continuous ticking noise. The car doesn't overheat, has no bubbles in the radiator, and the oil looks normal. Any help would be appreciated, thanks.

bluebeastsrt

You didn't say how many miles were on the car but those are all acceptable numbers. It doesn't sound like your head gasket is leaking. The ticking noise could be something as simple as a exhaust leak. As far as the miss, rule out the simple things first like plugs and spark plug wires distributor, etc. Good luck.

94ford5liter

The car has about 135k on it. I thought the rule was a 10% difference between the cylinders so I thought 19 psi between the highest and the lowest seemed a little high. The car has an almost new distributor, cap and rotor, and coil. I put new Motorcraft plugs in it not too long ago, but some of them looked pretty fouled already. I am putting new plugs and wires on it tonight so I'm hoping that helps. The wires would shock me when I even put my hand close to the distributor so I think they were pretty bad lol.

tinman

Those numbers are sure wide but thats still within specs...........