No fuel pressure & White Smoke out Exhaust - Car Starts fine

[briderx]

98 V70 GLT Turbo

I've been battling this issue for a while now. The exhaust smoke is white. It's not antifreeze, as I know what it smells like when head gasket goes. Plus, I've checked all 5 cylinders pressure. The smoke smells good.. A little rich, and oddly humid. When I drive the car, and I step hard on the gas, the car hauls just fine, but i leave a nice cloud behind me. I have read that you can tell if it's a bad o2 sensor by unplugging the one before the Cat and see if there's a difference. I figured I'd see a difference, but I don't. It runs the same, and exhaust is same as well. Does that prove that the o2 sensor is bad? The fuel pressure is odd as well. This is the first car I've ever had to drain the rail, but when I press the release valve, i get a couple drips. If I take the rail off, I can dump the fuel out.

When testing yesterday, I gunned it, and instantly got a P0422 code. I checked gas cap.. I didn't hear a hiss when removing it. I know there's a J-Hose that gets cracked and needs replaced, I haven't had a chance to check it, so I'm open to any/all ideas/tests/whatnot.

I have not unplugged the o2 sensor from the rear of the Cat yet. Just the front one.

[rmmagow]

Is your turbo healthy? Antifreeze levels changing at all? White generally means water in the combustion process I think.

[jblackburn]

I checked gas cap.. I didn't hear a hiss when removing it.

These cars don't keep that much pressure in the fuel tank to where they will do that, but I know what you're talking about with other cars.

I second the question about the turbo...does this car use oil? The GLT turbos have been known to let the seals go before the big T5 turbos. Dumping oil into the exhaust without burning it will cause this white smoke.

I believe the P0422 code does mean that the car's running rich, and the car may not know it (due to a bad front O2 sensor).

If you don't want to go through the effort yet of switching the sensors, yank off the negative battery cable, tap the brakes, and reconnect it. See if the car will set a front O2 sensor code now.

[jblackburn]

PS - You can take off the turbo intake air tube (it's a real pain) and wiggle the fins of the turbocharger in-out horizontal to the ground. If there is play in this direction, your turbo is in need of a rebuild. Some play up and down is normal.