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Hose off Vacuum Purge Switch?

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I can't tell for sure from the picture whether it's the EGR valve or the EVAP purge solenoid. If it is the EVAP purge solenoid, it has two hoses on it, one to the throttle body and the other to the EVAP canister. The one that goes under the beauty cover is to the throttle body. The one that goes down the firewall is to the EVAP canister. The EVAP canister is in the rear of the car on the driver's side, so that hose runs under the car for the length of the car. If it's off, it's a fire hazard because fuel vapor comes out of the hose where it ends, and you need to fix it.

The missing hose won't cause the P1645. It's an electrical test. In my 1997 FSM page 6-612, it says that the PCM grounds the solenoid line to turn it on, and the DTC will set if it doesn't see 12 Volts when the solenoid is off, or if the PCM fails to ground the solenoid. This DTC basically means that the ECS fuse, a 10 Amp fuse in the engine compartment fuse/relay center, is bad, or that the wiring between the solenoid and the PCM has a bad connection. Your photo shows a nice, clean solenoid with the connector off but I assume that you have already made sure that the connector is clean and that its contacts are in-place and tight. So, the fuse is the likely culprit. If not, check the voltages at the connector to make sure that you are seeing 12 Volts on the PNK wire when the key is on. Don't touch the GRN/WHT wire or its connector because that goes back to the PCM.

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I can see the two black hoses coming out of the canister in the back, one hooks up to what looks like a gas line.. when that line reaches the firewall, does it transfer into another black plastic line? I'm having a really hard time finding this SOB..

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I'm almost certain I'm missing a hose on my vacuum purge switch. Where is this hose routed from - where can I find it so I can reconnect it?post-14652-127739998051_thumb.jpg

Also, I'm guessing this is the main culprit to my P0300 and P1645 codes.

Here is my Evap solenoid & vacuum purge switch off my 97 Deville. The only thing wrong in your picture is that it is unplugged. It is not missing any hoses. Have you checked your fuel pressure? Save yourself a lot of trouble and start there. If the pressure is where it is supposed to be then check the other things. I spent 6 months doing what you are doing and it was a bad fuel pump. I know this was mentioned before on another thread but I did not see you comment on it. CHECK THE FUEL PRESSURE AND REPORT BACK.


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