I will try to stick to the points as i tend to ramble.

2004 Ford Explorer 4x4 v6 vin code k FLEX fuel.

bought with 130k miles 7 months ago.

Has 138k miles now.

It had the Engine Check Light for a little while but it ran great so i left it. (1 O2 sensor code at the time... i ran a can of seafoam through it and left the light on)

recently the mileage dropped so i had the codes checked again.

P0155 heater circuit malfunction b2s1
p0171 too lean b1s2
p0174 too leanb2s2
p1000 incomplete drive diagnostic

I inspected the 02 sensors... the b2s1 had a very small fray in 1 wire and the rear 2 were very rusty (probable original equipment).

So i replaced all 4 02 sensors with bosch. left the battery unhooked for 4 hours. I drove for about 30 miles and i got another code.

P0174 too lean b2s2.

Now. The Autozone computer system suggested i check the PCV valve and hose because it probably isnt a bad 02 sensor.

here is the strange part... the PCV valve is hollow... just a straight through empty piece of plastic. like the guts got sucked into the valve cover.

I called local ford parts counter, he went off of the last 8 of my VIN, and he said i should have a HEATED PCV valve ford#2C5Z-6A666-AA (motorcraft #EV-261).

This PCV has a 2 pin pig tail (an 8 inch, 2 wire, wiring harness) that the parts guy said on his diagram looked like it plugged in somewhere near the throttle body.

I cant find anywhere within 8 inches of the PCV that anything would plug into...?

possible questions.
1. anyone heard of the straight through no guts PCV?
2. anyone know where i plug the PCV valve pig tail into if in fact i am suppose to have the heated one?
3. what else should i look at? (because it ran fine for 6 months without the correct PCV valve).
4. maybe a vacuum leak somewhere??? i have no idea.

ANY and all replies are greatly appreciated.

Thank you for reading this far,

Randall

 

I'll have to check the service manual to see what it shows about a heated PCV valve. I've never heard of that, and I'm not even understanding what the benefit of having the PCV with a heater would be....

As for the diagnostic code, I'd be looking for a vacuum leak somewhere (possibly the hollow PCV, possibly the hose for the PCV, possibly the intake manifold gaskets, etc.). I'd also consider cleaning the Mass Air Flow (MAF) sensor with electrical parts cleaner or dedicated MAF Sensor cleaner. I would expect an issue with the MAF or vacuum leak in the intake air tube to trigger lean codes for both cylinder banks though.

-Rod

 

Thanks Shorod.

here is my new information.

the straight through one is on the right side (passenger) in plain sight (pretty much a perfect spot on the valve cover to put a pcv valve).

it is there to allow clean air in.

the pcv valve is on the left side (driver) WAY in the back and cannot be seen (darn near the worst place to put one).

it is "heated" and has a 2 wire harness going to it.

i finally found it through google and referencing my chiltons/haynes manual.

when i applied vacuum (mouth, suck and blow) to both sides of the pcv it allowed air through both ways.

to me that means bad but i cant find exactly how the "heated" part of it effects it's operation.

hopefully this will fix things but if not i will be cleaning the MAF and taking it in for vacuum leaks testing.

i am still open for suggestions and ideas!

Thank you,
Randall