Emissions control diagram?

[mtnman82]

Hello all! I just went to get a smog check and couldn't get the ccertificate becasue I have a check engine light on. Scan shows it's code P1450 (? unable to purge evaporative control system ?). So, I'm looking for a diagram of the evaporative control system for my 2001 Expedition. Could anyone point me in the direction of one? I ordered a factory service manual but it won't be here until next week sometime and I'd like to get this thing smogged ASAP.

Also, if anyone has any experience with this problem and could help shed some light on it, that would be greatly appreciated.

Guess I'm going to be checking the hoses/canister ... if I can find them.

 

[dougmcp]

There should be a vacuum Evap stcker under the hood on the radiator cover.
First thing I would do is check your gas cap to make sure it is sealling properly.
Secondly, after driving the truck, when you first turn it off remove the gas cap, if it hisses/release pressure your canister vent is blocked.

Your P1450 other possible causes:
-EVAP canister purge outlet tube (EVAP canister purge valve to EVAP canister) blockages or kinks.
-EVAP canister tube (fuel tank to EVAP canister) blockages or kinks.
-Fuel vapor elbow on EVAP canister contaminated.
-Restricted EVAP canister.
-Canister vent (CV) solenoid stuck closed (partially or fully).
-Plugged or contaminated CV solenoid filter.
-EVAP canister purge valve stuck open.
-Fuel filler cap stuck closed (no vacuum relief).
-VREF circuit open in fuel tank pressure (FTP) sensor.
-Damaged FTP sensor.

 

[mtnman82]

Thanks for the reply doug! No hiss from the gascap, I checked today - but I'm not sure I drove long/far enough today. I'll drive a good 10~20 minutes and check. Thanks for the list! I'll look for the diagram under the hood.

Looks like I lost the gas gauge now... Don't know if I touched something I shouldn't have?

Is the big round thing (~4" diameter, 12+" long) attached to the frame rail in this picture the charcoal canister? Doesn't look like what I see on the parts websites(?).

 

[mtnman82]

Oh, and this was a dealer. I'm looking at the invoice and it says "ran pump system test plugged charcoal canister". Does this definitively mean it's the canister?

 

[dougmcp]

Is the big round thing (~4" diameter, 12+" long) attached to the frame rail in this picture the charcoal canister? Doesn't look like what I see on the parts websites(?).

Yes, that's what it is and they look like this in the parts catalogs:

 

[dougmcp]

Oh, and this was a dealer. I'm looking at the invoice and it says "ran pump system test plugged charcoal canister". Does this definitively mean it's the canister?

It's either the canister, the vent or the solenoid.

 

[mtnman82]

Got the canister off, along with the solonoid & vent hose. A bit of a pain, and I had to lower the spare tire to wiggle the canister out, but no big deal.

Hose is clear. I can blow thru the solonoid with no power applied, if I apply 12v to the terminals I hear a click and I can't blow thru anymore, so I assume it's OK. I can blow thru the canister, but it is difficult to do so, so I guess I'm off to find one (hopefully locally today).

I haven't seen any DIY's on this board... Would a DIY on replacing the canister be useful here?

 

[mtnman82]

Well, got a cannister from Big A for ~$130 and put everything back together. You need to pull the solonoid and the 90 degree fitting out of the old cannister and insert into the new one. It helps to lower the spare tire too.

I cleared the codes and have driven it around some over the past couple days. Probably ~50 miles, around town thru highway speeds. No codes have popped up, but my scanner says its still waiting to complete the 'CAT' and 'EVP' tests, so won't give a green light on passing emissions.

Anyone know how long it will take to complete these tests? Can I take it in to get it smogged as-is, or do I need to drive it until these tests are complete?

 

[dougmcp]

I'm not sure if the smog place scans for ready codes or not, why not call your smog guy and see what he says?
The readiness codes need to go through a few heat and cool cycles and I would think it should be OK soon.

 

[outkast]

Illinois claims 10 key cycles with at least ten minutes of run time each cycle.