Smell of Gas vapor and obdII P1451

M

mk8fanatic

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I did a lot of searching on here and cant find out much about the emissions vapor canister and whatnot under the passenger side fender well.

The problem on this gen2 is that it smells of gas vapor as you drive the car, and it has an OBDII code P1451.

I have replaced all the injector Orings And cannot see any leaks what so ever. I even inspected for a leak behind the pass inner fender well to be sure that the fuel lines/filter and all else was dry..
I recently bought an OBD2 tool that read code P1451 as EVAP Control System Canister Vent Solenoid Circuit Malfunction..
Can not help to think that this canister deal may not be letting the gas vapors through to motor so it just keeps purging it off..am I on the right track?

Has anyone had this unit go out? Or can it be cleaned up? What exactly is this called in case I need to find one? What fuses or relay would be attributed to it?
 
That code relates to a circuit malfunction for the EVAP control solenoid. See here.

A code P1451 may mean that one or more of the following has happened:

  • VPWR circuit open
  • Damaged canister vent solenoid
  • Canister vent solenoid circuit open or shorted to ground, power, etc.
  • Damaged Powertrain Control Module (PCM)
Click to expand...
 
STOP "topping" off your gas tank. :D This kills your evap canister and all the solenoids.

If you need help trouble shooting let us know. Most likely the canister solenoid is damaged.
 
I haven't had more than half a tank since I got this car...saves on the weight:wink:

Furthermore, after more research it seems that the purge valve solenoid mounted with the vapor tank is shot...at least from what I can tell.

What really surprised me was that the vapor canister looked as though it were sealed and with only one vacuum line attached :confused:
I mean what good would that do?? straight off a sealed plastic tank to the intake? It had like nothing in common with the main vapor line and purge valve at all.

And lastly...I do believe that my OBDII code is from the bad purge valve but I
could find nothing at all under the fender that would any way vent the vapors
out into the open air via some type of pressure valve.
So I dunno if thats where the strong gas vapor odor is from or not..:mad:

Anyone know if there is anything like that in the rear of the car?
 
I don't know if the Gen2 changed from the Gen1 EVAP system, but on my '93 there are 2 lines atop the charcoal canister. One goes to the vent line for the gas tank and the other is to the throttle body vacuum via the purge solenoid.
 
This 97 has one large line from the tank to the purge valve then to the intake. Then the purge valve has one other smaller vacuum line that goes to the climate control unit in the car?? Then another small vacuum line from the intake to the vapor canister...

You know, the more I think about it it seems like someone has poked around in there and got it all wrong.

If anything that smaller line off the side of the purge valve should go to the canister...and the climate control unit should come right off the intake..

From the basic info and diagrams I can find on these systems It would make more sense for the vapor canister to collect and store vapors off the fuel tank when the purge valve is closed "ignition off"
then when the purge valve in open "ignition on" it would suck it out of the vapor canister through the purge valve and then on to the intake via large tube.

Tomorrow I will try and look how the other 97 is hooked up...
 
The climate control unit should get its vacuum right from the intake through a check valve. It should not be associated with the EVAP system whatsoever. The large tube from the canister should go to the throttle body and tee into the PCV vacuum line.
 
On my 95, the vacuum line for the a/c was tee'd off of a main line that ran behind the throttle body.
 
After inspecting my other gen2 I found that they are both the same, and that one of the two vacuum lines from the back of the intake goes to the canisters one and only one plug with a Tee at the fire wall going to the Climate control. The second line goes straight to the side of the purge valve.

Guess the canister and the purge valve are both part of the evap system but do not directly relate to one another.
I did take apart the purge valve and it seems that the smaller vacuum line would
aid,help, or insure the diaphragm to pull back and open the main larger line.
The line that goes to the canister could only catch unburned vapors in the intake when you cut the motor off. Then when you start the motor it would suck out the remaining vapors in the canister and provide vacuum to the Climate control.

I will order a new purge valve and hope this will fix the OBDII code because it does have an electrical solenoid that may be fried.

My only concern is that there may be more the this system that I can not find.
Please take a look at this Rockauto link...and tell me what you guys think.look under Emission...then Vapor canister and Vapor canister purge valve.
The vapor canister isn't even what this one under the right fender looks like...

http://www.rockauto.com/dbphp/mak,LINCOLN,1998,MARK+VIII+LSC,1316163,4.6L+281cid+V8+FI+%28V%29

I found that purge valve all well and great, But under vapor canister they show a different CANISTER,AUX EVAP EMIS F6DZ-EA; SOLENOID.

Anyone know where this is on the car? I don't have access to a lift and haven't poked around back near the fuel tank.
Is there an access panel of some sort under the rear seat?
 
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Jamie could help you emensly if you feel like giving him a call. Plus, you could buy a cheap used one from him at over half the cost of new parts. These things hardly EVER fail.

Here are some pics/info from the archives though.........

PURPOSE
The Evaporative Emission (EVAP) canister purge valve is in-line with the evaporative emissions canister and controls the flow of fuel vapors out of the evaporative emissions canister

OPERATION
The EVAP canister purge valve is normally closed. When the engine is shut OFF, vapors from the fuel tank flow into the evaporative emissions canister. After the engine is started, the evaporative emission canister purge valve is engaged and opens, purging the fuel vapors into the engine. With the evaporative emission canister purge valve open, vapors from the fuel tank are routed directly into the engine.

Located in one of the front fender wells......
EvapPurgeValve.gif


Electrical......
Evap.gif




PURPOSE
The fuel vapor is emitted through the evaporative emission valve and is stored in a carbon-filled evaporative emissions canister.

OPERATION
Vapors from the evaporative emissions canister are vented through tubes and hoses to the engine.

Located under the trunk I believe.
EvapCanister.gif
 
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Awesome! looked under the spare tire and found that rack holding all the missing parts to the system.

No wonder why I smell such strong gas vapors!
They have the vent tube that comes off the vent solenoid going right up into the body:rolleyes:

I took the diaphragm out of the purge valve to make it open all the time until I get a replacement. That should solve the vapor venting business!

Now If I could just get the cooling fan and A/C back :(
 
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