Along the lines of PureEnergy's post (earlier today), I just performed a compression test on my 1996 850 Turbo w/auto trans and have some concerns/questions about the compression numbers. Test parameters: Warm engine, all plugs removed, fuel injectors disconnected and coil disabled.
Cylinder #1: 137
Cylinder #2: 137
Cylinder #3: 137
Cylinder #4: 138
Cylinder #5: 139
It took 40 engine revs (approx), per cylinder, to attain these numbers. Call me crazy, but seems way too long. I then added a couple squirts of engine oil into each cylinder and re-tested...not much difference:
Cylinder #1: 140
Cylinder #2: 142
Cylinder #3: 140
Cylinder #4: 141
Cylinder #5: 140
Volvo says the pressure should be: 156 - 185 psi.
Except for weak "off-the-line" performance, the engine runs great with overall MPG of 21. Idle is perfect, revs freely and does not smoke, although I am adding 1 quart of oil every 3-4 weeks. I have replaced all the ignition components, induction hoses, belts, vacuum lines, coolant and hoses, recent oil & filter change, and replaced trans fluid. I am using dino oil because I have not replaced the slightly leaking oil cooler hoses yet. Once done, I plan to use Mobil 1. All sensors are OEM and appear to be working (no MIL).
What conclusions can be drawn from all of this? I appreciate whatever suggestions anyone can offer.
Greg
|