Code P0446

98 Winstar 3.0 engine, 227K

Have had the code off and on since we have gotten the vehicle, but lately it returns after driving approxx. 3-5 miles. I removed the connector and made sure the connections are good on the canister vent solenoid. Also made sure the solenoid worked by applyinng 12V to the solenoid and it clicks whenever power is applied, plus I checked the wiring to make sure there is not a short to ground on the wire going to the PCM and also the driver does not seem to be bad.

When I removed the canister vent solenoid from the cannister and line going to the gas tank I found a fair amount of very fine dust in the line from the tank into solenoid. Would the dust be coming from the canister or from the line coming from the tank???

EDIT: After doing more research I find that the line I am speaking of does not go to the gas tank from the vent solenoid, from what I understand there should be a filter for the fresh air to enter the canister vent solenoid on that hose. Any ideas where this filter is located???

Any thoughts, thanks

Hi Larry,

it might be unrelated but I had a p0441 code in my Grand Prix which is very similar to your problem. I kept chasing it for a long time and the code would return after some time; in the end I ended up replacing every single rubber piece in the EVAP system and that seemed to take care of it.

I never found any carbon in the Grand Prix but did find some carbon build up in my Lincoln which has the exact same configuration as the Windstar so it might be normal, just make sure the lines aren't completely obstructed like my Lincoln was.

Finally I do remember the line running form the purge solenoid at the firewall to the intake manifold in my Windstar was so bad that I could even use it instead of chalk so I replaced it as a cautionary measure.

In a few words, make sure the lines are OK and pay special attention to that specific rubber line (I think it's 3/8").

Oscar.

I just checked Mitchell on Demand for the '98 but does not mentions anything about a filter. I checked the manual I have for the 2000 and mentions a dust separator, which I think is the one you're talking, attached to the side of the canister bracket.

Oscar.

Thanks Oscar, Today I drove the vehicle 30 some miles with several drive cycles and no light today. (Longest it has gone with turning on the liigt is some time. The one thing I have not tried is a new cas cap.

Possibly the cleaning of the dust from the line and solenoid plus driving it Sunday may have got the solenoid plunger freed up so it is opening and closing properly again.

Time will tell, and I will also check hoses again for problems.

The code did reappear again.

This time I installed a used purge valve under the hood (under cowl) and have driven for over 200 miles without the cel on or any pending code, so I believe I have finally won on this code.

Nice work Larry,

Hopefully it will stay that way; you can take a look at the system monitors if you have a capable scanner, that way you'll know, instantly, if the EVAP monitor has passed and have peace of mind.

Oscar.