I tried to find a PCV valve for my 2005 Expedition but can't. The one I have has wires (2) coming out of it but the ones on the market don't. I measured the resistance between the 2 wires and it's pretty much zero. Does this mean it's broken?

I check the elbows/hose on it and didn't find any crack. I replaced the O-rings inside the elbows (2 on each side).

The problem I have with this car is when it's first starts: it makes tractor kind of noise and will disappear in about 5 seconds. I did get P0171, P0174 code but not sure if it's related.

Anybody had similar problems before?

 

The PCV valve on the '05 is a non-serviceable part and is integral to the valve cover on drivers side. In order to replace it, you will need to replace the valve cover. The "valve" you describe with two wires is the heater element, as the '05 uses a heated PCV system. It's not an actual valve. If it's not functioning, the PCM will throw a code on it so I suspect yours is working.

The lean codes you're getting may be either a dirty MAF sensor, or a vacuum leak somewhere. The throttle body has rubber gaskets you may inspect, plus the vacuum hose to the brake booster. There's a vacuum hose connected to the rear of the intake plenum all the way in the lower part on drivers side, try to get either a camera back there or a hand and check if it's still in place. Apart from that, check all other vacuum hoses, and of course the hoses for the PCV to make sure there's no leak on those. Finally, it's not impossible that it is the intake manifold gaskets that are bad, but seems unlikely that it would be on both sides..

 

Thanks, Skauber!

Now I know why the insulation on those wires melted pretty bad: it's a pretty powerful heater.

I did clean the MAF sensor with MAF cleaner but can't be 100% sure it's 100% working. I will check all other possible leaking places later.

But none of these should cause the starting noise, right?

 

Depends on what the starting noise is. If it's a valve clattering noise, you may want to inspect your VCT solenoids to make sure they're not clogged or sticking. They're located on each side of the engine in the front of the valve cover, thingy sticking out with a wire connected to it. If it's a pinging noise which lasts for a second or two, it's usually the timing chain. Make sure you use a Motorcraft oil filter with an internal check valve to reduce that noise. That's usually the chain tensioners going slack and then taking a moment to build oil pressure to put tension on the chains again upon the first startup in the morning.

For the MAF, check it with a scantool if you can. Should show something like 6-7 g/s or similar on idle. Also check your fuel trims if you have that capability in the scantool. If you don't have a scantool, but you do have a smart phone (android) or laptop with bluetooth, you can buy a OBD2 bluetooth adapter (OBDLink MX is the best at $99 with full network support, but you can get by with a cheap-o chinese adapter for 20 bucks), use Torque (Android) or FORScan (Android (5 bucks), iOS (5 bucks), Windows (free)) to read the needed parameters.

 

Thanks, Skauber!

I think I can record the sound and post it here.

I do have a scanner and will check when I have a chance and let you know the readings...

 

Finally I have a chance to take a video of my Expedition starting:


You can hear it's pretty rough. I occasionally have "cylinder misfire" code and last time was #7 and after I moved the coil to #5, now I have it on #5. So I need to replace this coil for sure.

Other than this, I have 1.2 lb/min. MAF reading, which is about 9 g/s. It will go higher with driving. So it's OK?

 

The video is set to private, so can't play it.

9 g/s on maf at idle sounds slightly high, is it at 700 rpm or so? Mine shows about 7 g/s, and I recently replaced mine. It was showing slightly high as well, but the reason I replaced it was because it had a crack in the housing, after replacing it I actually gained a little on fuel economy and the truck seems more responsive. The old one had been cleaned, so not sure why the difference. Might be that being 10 years old, it simply goes slightly out of spec...

 

Sorry, I changed it to public now.
Since it's cold, the idle may be higher than 700 rpm (you can tell from the video). Maybe that's the reason for higher air flow.
I ordered a coil today. But I don't think that's the reason either because that code won't show up most of the time.

 

Do you have a bluetooth OBD dongle on a Android or Apple device? Try to use the app FORScan, it's 5 bucks on Play Store or App Store, to see if it can read some more manufacturer specific codes. It may show other codes a generic scantool does not, like knock sensors, intake manifold runners and what not..

But, in your case, I would recommend you check the gaskets on the throttle body, remove the air filter box and you will find the throttle body under it, held on by 4 screws. There's a small gasket between that and the intake, plus a thicker rubber gasket on the airfilter which squeezes over the throttle body. The latter one was bad on mine..

 

Any particular brand dongle? What about the noise? It sounds like knocking/missing?
I will check that gasket. Thanks!

 

I would recommend the OBDLink MX, but it's 99 bucks on Amazon. If you think it's too much, then there are cheaper alternatives, but I haven't tried any personally to recommend them. The OBDLink one is one of the fastest and best adapters with full MS CAN support

 

Thanks! That's still much cheaper than the one I have now. I can sell this one and buy that one and all the software for different cars I have...

 

It's a very capable adapter, I've even programmed PATS keys on my Expy with it..

 

Sorry to hi jack your thread. But will a bad PCV valve cause about one quart of oil lose per 1000 miles?
TIA,
Tim

 

No, the PVC valve is at the top of the engine and has a splash guard under it. While it's possible for oil vapors to get into the PVC valve and cause build-up over 10s of thousand of miles, it's not going to suck down a quart every 1,000 miles. For you to lose a quart that often it's more likely worn valve guides and seals or worn piston rings.