Piston Slap: A Panther Love (EVAP) Purge?

Sajeev Mehta
by Sajeev Mehta

Sam writes:

Dear Sajeev,

After reading TTAC for many, many years I succumbed and finally got me some panther love. It blows my mind that Ford can make such a well-balanced, corner-carving sedan and then never sell it to civilians. I traded my 2006 Mazda 3 for a 2006 Police Interceptor Crown Vic (170,000 miles). The aftermarket exhaust makes it growl and it parts the sea of entitled BMW drivers hogging the fast lane like a dream. Unfortunately, due to living in glorious urban hellscape that is Oakland, I have to pass smog regularly.

I have a check engine light code P0443. I replaced the evap. control module that was supposed to fix it and surprise, it didn’t. The internet says it could actually be my fuel cap. I replaced the gasket on the fuel cap and the check engine light is still on.

The next option seems to be to replace all the lines to my fuel system. This seems crazy, just because of a small vapor leak. This is not an expensive car (est. $1,500) and it was only meant to be a quick fling before I buy my Mazda CX-5 middle-aged nerdy dad car. Is this something I or a mechanic could fix for less than $500, or is this the death knell for an old police cruiser?

Sajeev replies:

Replace all the fuel lines? Who on earth told you that? There can be two sensors and inspect/replace all vacuum lines that look the least bit dry rotted, gooey, cracked, etc.

Sam answers:

I actually replaced both the solenoid and the canister purge sensor. I have not replaced the fuel tank pressure sensor. That might be the offending part. It looks like I have to drop the fuel tank to get to it which sounds like a pain in the ass, but it is worth a shot. It might be something I can have my mechanic do.

Can I just buy vacuum lines online? Those are the lines I thought would be difficult to replace. The one last thing I thought about changing is the charcoal vapor filter because it also takes forever to fill up the gas tank.

Sajeev concludes:

Ah-HA! You didn’t mention that filling up the tank takes forever!

Maybe you are also getting a P0445 code like this Panther owner did upon further inspection? Perhaps this thread shows the diagnostic tree you must branch out for? I’m not gonna guess: who knows if the vapor management valve (or whatever its called) failed or if you only have bad vacuum lines.

Therein lies the rub: paying someone for a proper diagnosis was a better idea than the unnecessary stress of throwing parts at a problem. If the vacuum lines pass muster, I would still enlist a proper mechanic for a proper assessment.

[Image: Shutterstock user Madcat_Madlove]

Send your queries to sajeev@thetruthaboutcars.com. Spare no details and ask for a speedy resolution if you’re in a hurry…but be realistic, and use your make/model specific forums instead of TTAC for more timely advice.

Sajeev Mehta
Sajeev Mehta

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  • S197GT S197GT on Mar 24, 2018

    i hope the first part you threw at it was a $10 or less fuel cap. fixed the vacuum-related CEL on my '01 Ranger. Can't remember the exact code I pulled, though.

  • JK43123 JK43123 on Mar 30, 2018

    We had the same code for my wife's 09 Grand Marquis and couldn't put gas in it. Replaced the canister purge solenoid and now it's fine. Replace fuel lines?

  • Kwik_Shift_Pro4X The push for EV's is part of the increase in our premiums. Any damage near the battery pack and the car is a total loss.
  • Geozinger Up until recently this was on my short list of cars to replace my old car. However, it didn't pass the "knee test" with my wife as her bad knee makes it difficult for her to get in and out of a sedan. I saw a number of videos about the car and it seems like the real deal as a sporting sedan. In addition I like the low price, too, but it was bad luck/timing that we didn't get to pull the trigger on this one.
  • ToolGuy I agree with everyone here. Of course there are exceptions to what I just said, don't take everything so literally. The important thing is that I weighed in with my opinion, which is helping to move things forward. I believe we can all agree that I make an important contribution (some will differ, that is their prerogative). A stitch in time saves nine. Life isn't fair, you know. I have more to say but will continue at our next meeting. You can count on that, for I am a man of my word. We will make it happen. There might be challenges. I mean, it is what it is. This too shall pass. All we can do is all we can do. These meetings are never really long enough for me to completely express all the greatness within me, are they? Let's meet to discuss. All in a day's work. After all, Rome wasn't built in a day. At the end of the day, I must say I agree with you. I think you will agree. When all is said and done, there is more said than done. But of course that is just one man's opinion. You are free to disagree. As I like to say...(I am working on my middle management skills -- how am I doing?)
  • Golden2husky Have to say he did an excellent job on the C7, especially considering the limited budget he was given. I am very happy with my purchase.
  • Marty The problem isn't range; it's lack of electricity in multi-unit building parking. All you need is level 1 - a standard 120v wall socket - and if you're plugged in 10 hours overnight you get 280 miles per week or more. That's enough for most folks but you can use public charging to supplement when needed. Installing conduit circuits and outlets is simple and cheap; no charge stations needed.