P0442 Evap Leak - 2006 Explorer XLT 4.0L

[Line82]

Hello, I have an '06 Explorer XLT with a 4.0L with DTC P0442. I can hear a pinhole leak coming from either under the hood or floor board area. I am not sure if it has to do with the Evap code, but I bet it does though. Are there any common problems with vapor hoses leaking or something similar?
I have replaced: gas cap, evap purge valve (located under the hood), the vacuum supply line for purge valve, A/C check valve (for possible supply vacuum leakage causing the code?)
The only line I haven't replaced is the fuel vapor line running to the purge valve (IF in fact that pinhole leak is coming from the evap system, and not another system)
Is the Evap solenoid (located on the frame rail down by the fuel tank) known to go bad causing this code?
Thank you for any information you may have.

 

[brown_strain]

I don't think I can hep, but let be know if you figure it out! I replaced both the vacuum side solenoid and the purge one back by the fuel tank. Still have the code. .. must be a leak in some line somewhere. Dropped the tank, messed with the fill hose, couldn't find it.

I have the dash vacuum leak too, but it's intermittent. Only sometimes when going up Hills under reduced vacuum dothe dash vents shut off. Other times its fine! That's after replacing the vacuum check valve.

Not sure if the two issues are related or not, but I have very similar symptoms to you, it sounds like.

 

[Line82]

I'll let you know as soon as I figure it out. I may have to break down and take it to the dealer for at least diagnosis. There are 2 things that I HAVEN'T changed yet. 1) The vent solenoid down by the tank and 2) the fuel favor supply hose that runs from the tank to the purge valve (located under the hood.)
I HAVE replaced 1) the purge valve under the hood 2) the rubber vacuum supply hose that runs from the purge valve to the intake 3) the A/C check valve.
I have tried different things to see if the pinhole leak may be coming from the vapor supply line but have had no luck determining it. I will be ordering the vent solenoid in the next week or two and see if the code clears. But I am thinking that it's the pinhole leak that's causing the code. But I don't want to guess and replace the vapor supply line as it runs $150+ at the dealer (can't find it aftermarket).

 

[Flag Gibby]

Just realized that you are still working on the same issue that you posted on back in May... Track down that leak under the hood first before you do anything else. Use an engine stethoscope to find it.

 

[Line82]

Yes, still working on it. I had other DTCs and have recently cleared them up. I would definitely like to do that, but I do not hear the leak until the engine is under load. I think the smoke machine may be the only option. I will continue to look and listen until I am sure that I cannot hear anything even faintly with the stethoscope.

 

[Flag Gibby]

So if you hold the engine at say 2500 RPM in park you cannot hear it?

 

[Flag Gibby]

So if you hold the engine at say 2500 RPM in park you cannot hear it?

Edit: What side does it sound like it comes from?
....dang using the IPad and hit the wrong button.

 

[Line82]

It sounds like it's coming from out of the engine compartment passenger's side. Definitely not coming from under the dash. I have checked the EGR vacuum lines and they look ok. I have checked the vacuum lines coming from the firewall - they look ok too. I lost sight of the fuel vapor metal line as it went behind the engine that runs from the purge valve to the tank. I'm starting to think that this vacuum leak may not be P0442 related. As for the DTC code, I ordered a Canister Vent Valve (mounts to the frame rail down by the tank) and will be installing that as soon as I get it.

 

[Line82]

I can hear the noise at different RPMs, and it does fluctuate with engine RPM. I cannot pinpoint exactly where it is coming from at this current time, but I will look into it again even more.

 

[Line82]

I'm hoping its not an intake plenum noise or anything of that nature. Intake gaskets look dry even though vehicle has 128K miles on it. She's a great runner

 

[TexasArmadillo]

My 442 code was caused by the fuel neck problem. Although I was displaying a different code before the 442.

Juggling more fur balls than a constipated cat.

 

[brown_strain]

Where abouts in the fuel neck? Could you see it visually? These newer models don't seem to have the plastic liner that caused problems on the older trucks. I did some serious snooping around my fuel neck and couldn't see anything wrong....but.... Who knows if I just couldn't see it....

 

[TexasArmadillo]

I have the capless fuel inlet. My original code dealt with my fuel cap being loose. I tried to change out the fuel cap device but it did not work. I did receive a letter from Ford saying that a small leak in one of the connection can cause the code. If I had to guess it is the vapor return line.

If you need a picture of the assembly I can post one.

Juggling more fur balls than a constipated cat.

 

[brown_strain]

Line82, did you replace the purge solenoid valve back by the tank? Did that fix your issue?

 

[Line82]

Hello,
Yes I did but with no luck.

 

[Flag Gibby]

Well, if you still have the P0442 code it sounds like you are going to have to do the smoke test at some point so you can find the one piece of tubing that has the pinhole leak. At least your problem doesn't cause drivability issues so you can just try to ignore the warning light on the dash.

 

[Line82]

UPDATE: I took the truck into my local Ford dealership and they did the smoke test: Come to find out that the vent solenoid that I replaced on the frame rail down by the tank was faulty all this time and itself was leaking. I had the dealer put a motorcraft solenoid on, they retested, retested o.k. It was a Dorman valve that I originally installed too.. I guess some things are engineered to use Motorcraft and nothing else Reminds me of when I replaced the thermostat: the aftermarket thermostat ran the engine too cold, and I got a ck engine light. Put in a Motorcraft thermostat, engine got to temperature

 

[Line82]

UPDATE: I took the truck into my local Ford dealership and they did the smoke test: Come to find out that the vent solenoid that I replaced on the frame rail down by the tank was faulty all this time and itself was leaking. I had the dealer put a motorcraft solenoid on, they retested, retested o.k. It was a Dorman valve that I originally installed too.. I guess some things are engineered to use Motorcraft and nothing else

 

[Flag Gibby]

Glad to hear that your problem is finally resolved.

 

[brown_strain]

Thanks for reporting back, glad you got it squared away! I have replaced my vent solenoid with a dorman unit, maybe there's something to that! I used to have no problems with the aftermarket parts like this, but I just had two non-OE electrical parts not work out of the box on our Honda Odyssey. After my experience and yours, I'm starting to think its worth the extra $$ for the OE to avoid multiple purchases and more troubleshooting...