When I removed my heater control valve (vacuum operated) I plugged the line with a golf T and I never received a code for it, unless the yellow line has some kind of sensor.

I'll also note that after my drive, i took off the gas cap and didn't hear a 'hiss' sound. If this fixes my gas mileage problem without throwing codes, I may just leave it that way.

 

The heater control valve wouldn't have a sensor of any kind _ no need for it.
The 2 wired plug that operates the solenoid on that EVAP purge control valve detects if there is a vacuum leak or if there is no vacuum.
You should get a code eventually, it would be very odd if you didn't.


If you didn't get a code, then there is something certainly not functioning right.

 

I did leave the evap valve electrically plugged in, I believe. I'll double check.

 

in2 fx4

this was 1 of 2 links posted on msn`s webpage in the auto section

Automakers to gearheads: Stop repairing cars - Autoblog

a second link i cannot find now , the big 3 were in senate hearing regarding several engines of each manufacturer were not meeting the advertised mileage ratings listed the window sticker

ford was on the hot seat because of several after market tuners who were ordered to testify on behalf of them selves

1 specific tuner stated he was able to eck out almost 28 mpg`s out of the 4.0l v6 engine when ford only listed it as 19 mpg ( or close to those numbers ) with his custom tune

ford / chevy / chrysler were testifying back in the spring in senate hearing

especially ford was again on the HOT seat for the 4.0 v6 engine constantly failing emissions testing not to mention fuel economy ratings

but you had to scrolol down to the msn`s auto page to follow the links

 

Started the truck again, and it doesn't smell gasious anymore with the evap system disconnected. I think we've found the golden goose!

 

if the truck runs perfectly fine with the EVAP dis-connected

i would just leave it dis-connected , your fuel economy might go up

 

That's what I'll do if this works. Why replace the purge valve if the only thing that changes is my fuel economy?

I'll do it more elegantly, though. Long, clear hose with grade 8 bolts isn't my final plan, lol.

Still no check engine light.

 

keep an eye on your mileage and report back after the second tankful

this will provide a basis for analysis

 

Will do. I've got a quarter so far, and I plan on refueling here soon.

 

I've got (or had) half a tank right on the dot. Didn't go full tank because gas is a bit high right now and I'm pinching pennies. Then reset the trip odo.

So far I've got about 20 miles on it, driving as normal. Still no check engine light, still doesn't smell gassy on startup and she runs fine. I'm hoping I can push 150 out of this half a tank. If I can do that, that tells me I'm on the right track.

if this does fix it, I'll just leave it plugged off. If that fixes it, why buy more parts?

 

If the EVAP system is/was the problem, I wonder what part of it is broken ?
The world may never know...

 

Granted, I didn't test the valve with voltage to see if it opened, but it did pass the tests my service manual lists. I don't think that part in particular is bad. I think it's something closer to the tank. Either way, it this fixes it, heck yeah. I'll use the black hose that was originally connecting 'em, then stuff some cheap two-cent half inch bolts in there with a couple cheapie hose clamps to seal it off.

Yeah, yeah, environment and all that. But if my truck is more efficient with it disconnected, I say win. Although it makes me wonder, shouldn't pressure be building in the tank with it disconnected from the engine, accompanied by a 'hiss' when the cap is removed?

Here's hoping!

 

the tank will only hiss when the vehicle has been parked for many hours in hot weather

the gas cap has a air suction valve , and it only opens when fuel is being drawn from the tank

 

I bet there is more evaporation of fuel into the environment when people fill up then what's coming from peoples gas tanks.

 

cameron you did / did not happen to replace your fuel pump recently

if you did , you may have switched the evaporative canister hose with fuel rail pressure return hose nipple on the fuel pump housing

both of those nipples are the same diameter

 

I never did the fuel pump, and as far as I'm aware, my Ranger doesn't have the return system anyway.

Hoping it doesn't, anyway. Last thing I want to do is drop the tank or remove the bed.

 

the fuel filter has 3 ports

fuel pump to filter
filter pressure relief return
filter to engine

if you bought this truck used , the original owner probably mixed up the 2 other nipples

your intake manifold was creating a vacuum and then began drawing fuel from the tank through the evaporative canister , up through the evap hose and into the intake manifold

i remember now , about a guy who owned another jeep cj , he replaced the fuel sender , but mixed up the 2 nipple ports

he connected the evap canister hose to the fuel return nipple , and the fuel return hose to the evap nipple

the fuel return nipple and tube runs down along side the fuel pump pickup tube

 

My filter only has two lines. I replaced it last fall. My father's on the other hand has three.

 

hmmm strange how the intake could suddenly start drawing fuel from the tank through the evap system

 

Still might be worth a look to see if things are right _ even more so if it's been doing this you've had it.

 

When Ford switched to the Returnless Fuel system there were a few years that still had the Return line on the fuel tank, these used a 3 line fuel filter, the extra line sent fuel back to tank on the Return line.

 

I'm not sure how I could have messed up the fuel filter. One line going in, one line going out and to the engine, and it's pointing the right direction. The lines are dry, too. No fuel seeping out.

 

the 3 line filters have the pressure relief valve inside the filter
you might want to recheck the frame rail cameron

i think the previous owner may have capped off or removed the return line from the fuel filter

 

I'll give it a look tomorrow.

 

Searched around under the truck and didn't find any orphaned lines. Also couldn't find anyone who provides a 3 port fuel filter for my Ranger.

I did, however, realize something. If that evap valve is leaking, it's not going to help me by blocking off the valve's exit. So, I removed the outlet hose entirely and plugged off the evap line going to the valve itself.

Also, no change in mileage as of yet. Sure runs nice though. No gaseous smell either.