1996 3800 series II, elusive Vaccuum leak
04-24-2011, 09:36 PM
#22
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Yes, absolutely. The small o-ring on the valve and the larger one on the housing. Both are there and in place, as well as the spring. Is the pcv valve supposed to flow in both directions?
Would like to know more about that passageway that leads right into the crakncase. That almost seams like a bypass of sorts, but maybe not as it'* right in front of the throttle plate and not subjected to vacuum.
Would like to know more about that passageway that leads right into the crakncase. That almost seams like a bypass of sorts, but maybe not as it'* right in front of the throttle plate and not subjected to vacuum.
04-24-2011, 09:41 PM
#23
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It'* a one way valve, out of the crank case.
The port is in vacuum when the throttle plate is open. When plate is closed then positive pressure in the crank case would push gases threw.
The port is in vacuum when the throttle plate is open. When plate is closed then positive pressure in the crank case would push gases threw.
05-01-2011, 10:43 PM
#24
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Update Found the problem.
It was the front O2 sensor. Wish I would have replaced that sensor first. At least I got an education.
The last trip I took I got 2 codes, even though it was running better, both for the Bank 1 o2 sensor. Fuel trim numbers are now good except for the rear which is still 99%. Not sure where to go with that but the cat may be worn out. As long as it'* running well and my gas mileage is back I'll be satisfied. It'* running like it was prior to the intake job and the exhaust no longer stinks.
Never realised how important an O2 sensor really is. I will keep an eye out for high percentage fuel trim numbers in the future. Unbelievable how one sensor can make or brake the driveabilty of a vehicle.
The last trip I took I got 2 codes, even though it was running better, both for the Bank 1 o2 sensor. Fuel trim numbers are now good except for the rear which is still 99%. Not sure where to go with that but the cat may be worn out. As long as it'* running well and my gas mileage is back I'll be satisfied. It'* running like it was prior to the intake job and the exhaust no longer stinks.
Never realised how important an O2 sensor really is. I will keep an eye out for high percentage fuel trim numbers in the future. Unbelievable how one sensor can make or brake the driveabilty of a vehicle.
05-01-2011, 10:50 PM
#25
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The front O2 sensor tells the PCM what'* coming out. If that data is wrong the PCM will adjust. As they get old they clog up and then run richer and richer. Over time this kills the cat, and this is what the rear O2 is telling you.
05-15-2011, 08:42 AM
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I had a crack in my tube on a 1995 Bonneville which I sealed, but do you know if there is a washer like seal that fits on the ends of the tube when inserting it, because I found what looked like a dried up old hard plastic washer on the one end when I removed it.
05-15-2011, 10:25 AM
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It looked like a very thin hose washer, but was very hard and brittle. I did check the tube afterward by spraying carb cleaner on it and there was no difference in engine speed.