Evap System Problem
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Joined: Apr 2006
Posts: 731
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From: Las Vegas NV
Evap System Problem
Hello All:
I have an LT1 Evap System Issue that is really getting on my nerves. I have a 94 Fleetwood with the LT1/4L60E similar to the C4's.
The tank is over pressurizing. I've chased the lines and tubes from the tank to the front and all the tubing looks good. I checked the purge valve and canister and all looks good (my can and valve are behind the front bumper) I performed a vacuum test on the valve per the FSM, and it holds vacuum like the FSM states it should.
When I got to the purge solenoid on the intake manifold, I followed the FSM test for it. I get ample vacuum from the TB, so there isn't any issue getting vacuumm to the solenoid. However, the FSM states the solenoid should hold vacuum on the Can side. The one in the car leaked down....and so have all 7 of the new ones I bought from various places including the local Chevy dealer. The old one and the new ones are holding vacuum on the TB side of the solenoid but leak down on the Can side.
Even with the new solenoid in place, I'm still getting too much pressure in the tank.
Can anyone tell me if the information in the FSM I have is incorrect on the testing for the solenoid? I'm having a difficult time with the idea that 7 solenoids I've purchased are all bad.
Thank you!
Constantine
I have an LT1 Evap System Issue that is really getting on my nerves. I have a 94 Fleetwood with the LT1/4L60E similar to the C4's.
The tank is over pressurizing. I've chased the lines and tubes from the tank to the front and all the tubing looks good. I checked the purge valve and canister and all looks good (my can and valve are behind the front bumper) I performed a vacuum test on the valve per the FSM, and it holds vacuum like the FSM states it should.
When I got to the purge solenoid on the intake manifold, I followed the FSM test for it. I get ample vacuum from the TB, so there isn't any issue getting vacuumm to the solenoid. However, the FSM states the solenoid should hold vacuum on the Can side. The one in the car leaked down....and so have all 7 of the new ones I bought from various places including the local Chevy dealer. The old one and the new ones are holding vacuum on the TB side of the solenoid but leak down on the Can side.
Even with the new solenoid in place, I'm still getting too much pressure in the tank.
Can anyone tell me if the information in the FSM I have is incorrect on the testing for the solenoid? I'm having a difficult time with the idea that 7 solenoids I've purchased are all bad.
Thank you!
Constantine
