Check engine light stays on,not flashing,checked under hood,everythings ok.
I even cleaned the MAF sensor,light is still on damit!!!
This is the first time this has ever happened.
any suggestions ,to what may be causeing this ????
see ya,old retired guy

 

What codes are you getting?

 

And what year and engine.
With out any more info, it could be a hundred different things...

EDIT:
Just checked your other threads _ 06 3 Litre Auto...

As what Pete said, what code are you getting...

If it's running OK, it's probably something to do with your EVAP system.
Truck can run perfectly fine with that system not functioning properly, but that's a big guess.

 

X3 on codes. If you dont have a code reader, autozone can check the light for free. Write the code you get down.

 

Took it to Autozone ,found code P0456,small leak in EVAP system.
Now where hell is this small leak ????
old retired guy.

 

One of two things. It could either be an internal or external leak. An external leak means the gas fumes are being vented to the atmosphere.
An internal leak would mean that the evap solenoid, the valve that controls when the engine sucks off the vapors, is malfunctioning.

 

Where is the evap silonoid on a 06,3.0 engine????
old retired,guy

 

First, driving the truck with CEL(check engine light) on and code P0456 will NOT hurt anything, so truck is safe to drive.

EVAP system uses a running engines intake manifold vacuum to create negative pressure in the Gas Tank

When you stop to get gas and open the gas cap you should often here a "whooosh" noise as air is sucked into the gas tank because it had negative pressure from just driving the truck.
If you haven't heard this in awhile then yes you have a leak somewhere in the EVAP system

The point of the EVAP system is to prevent gas fumes from polluting the air we breath.
So this is an Emissions system like Catalytic converter

When you are driving the truck the computer will run tests on all the systems including EVAP system.
In one of these tests the computer increased the negative pressure in the gas tank and it didn't hold the pressure, so it "made a note" of that, by setting a code in memory but wouldn't turn on the CEL.

Next time you drove the truck(has to cool down) the computer would run another test on EVAP system, and if it also didn't hold pressure then it would turn on the CEL and set code P0456.

EVAP system is like this:
--------- = vacuum hoses

Intake manifold--------EVAP solenoid----------pressure sensor/charcoal canister------Gas tank

A solenoid is just an electric valve the computer can open and close, in this case, when it opens gas fumes would be sucked from the gas tank thru the charcoal and into the intake to be burned in the engine.

When solenoid closes then, if system is sealed, it should hold that negative pressure.

So EVAP code P0456 covers alot of ground, lol, slight leak

Gas cap seals the tank, so could be bad gas cap, they can be tested, "loose gas cap" often comes up when looking at this code

Filler and vent hose, where you put the gas in, they have rubber parts that can crack and so leak air or fuel.
Common issue in warmer climates

Any of the vacuum hoses

Faulty pressure gauge

Cracked charcoal canister

And yes faulty or leaking solenoid

So you could waste alot of time and money replacing parts that are not broke.
P0456 is just a general code that only tells you there "may be a small leak" because it could even be a faulty computer, lol, very very unlikely but still could be.

First thing I would do would be to get a short hose and a rag
Remove gas cap and put hose in gas tank, just a little into the neck then wrap rag around it to seal it.
Now blow into the hose, lungs can generate about 2psi pressure
See if tank can hold the pressure
And LISTEN
You may hear air escaping

Don't use an air compressor or you WILL blow off fittings on the tank, lol.
get a grandson or neighborhood boy with young lungs to help out, :)

And just as a "heads up", CEL will NOT go off after you fix the system.
Computer can not be reset for emissions codes, computer must run 2 successful tests of the EVAP system before it will clear the code and turn off the CEL.
There is no way to force it to run the test, but it will run the test each time engine is fully warmed up because of the code.
Then engine must cool down, below 100degF, and next time it warms up it will run another EVAP test.
A "drive cycle" is when engine coolant warms up to 190degF and then cools down to 100degF, that = 1 drive cycle
Computer needs 2 or 3 drive cycles to clear emissions codes, assuming tests are good
For this code try to keep gas in the tank below 3/4 and above 1/4 after any repairs, seems to help pass the testing.

 

Thanks for all the info.Don't quite understand the blow in a hose thing,if air comes back out
of the tank,does that mean,new gas cap ??
Where is EVAP solenoid located on my 3.0 engine ???
thanks

 

Moves around year to year so can't say, no one could unless they had changed one on a 2006 regular cab Ranger 3.0l, not even a Ford dealer mechanic could, unless he had changed one.
Shop manuals don't even list locations, except vaguely
Best guess would be drivers side of engine bay, it will have 2, maybe 3 hoses(3rd hose is a vent) and a 2 wire connector.
1 of the hoses will run to intake manifold

Not trying to be funny that's just the way it is on cars and trucks

Google: 2006 ford ranger 3.0l evap solenoid location

I didn't see much but didn't read everything either.


Hose in the gas tank
If you wanted to find a leak in a balloon you would blow it up and see if and where it was leaking.

Same idea, you blow into the gas tank and see if it is holding pressure or if you have to keep blowing into it.
If you have to keep blowing then you may be able to hear the leak point, i.e. filler/vent hoses

Gas caps can be tested, try auto parts store

 

pfisher.
Go to RockAuto and plug in your year and engine.

Here's a link hopefully should work.

2006 FORD RANGER 3.0L V6 Vapor Canister Purge Valve / Solenoid | RockAuto

The link works, and judging from the look of the bracket it's in the same position as mine. It's basically where Ron said it is, it's above the drivers side fender-well just forward of the fuse junction box.
One of the lines coming out of it will be hooked up to the intake manifold _ down low and near the front of the manifold _ the line will be as big around as your thumb.

I have the same code on mine truck, I haven't had a chance to trouble shoot it though, but I'm thinking (when it's time) to take it to the Ford dealer and have them do smoke test.
There is also a line that runs from the valve to the fuel tank area and there are many unions on it, I can see them clearly because my engine's out.
Any one of those unions can be the cause _ a smoke test will tell you where the leak is.

 

Thanks guys,I looked at the picture of it on rockauto ,I recognize that conical ****.
I'll look at it today,It's still dark here.I'll start it up and spray some MAF cleaner on it,and see if anything changes RPMs wise.
see ya

 

I used 1\2 can of MAF cleaner on every hose in engine bay,also the evap silonoid.
No change in RPMs whatsoever. Went to auto zone bought a new fuel cap.
Came home,disconected battery,fired her up,NO CEL !!!!
When i drive around today,we'll see if light comes back on.
I HOPE NOT.!!!
see ya ,old retired guy

 

That's good news

Thanks for the update

 

Is your filler cap a screw type or bayonet type ?

 

Drove around half the day,still no cel light.
I guess the gas cap was the culprit,around the cap was all dingy looking black stuff.
Must have been the leaking fumes.
see ya,old retired guy.



What is a bayonet type gas cap ??? Mines a screw on.

 

bayonet has two prongs that slide in to slots on the filler opening, when you twist it, it tightens cap down.

Popular on old tanks but still used, I am sure you had a vehicle with that type at some point in the past

 

The old dingy black stuff was probably what was left of the "seal"...

Interesting how they changed that, my 99 is a bayonet type, I guess Ford moved back to the screw type I 2006.
Maybe the bayonet type had a tendency to leak.

 

I used to drive for a limo service. Every vehicle I drove had a check engine light on. I'd report it to the boss and he'd tell me there's nothing wrong. I told him it made my passengers nervous. His reply....stick one of your business cards over it.

 

The biggest problem with electronic fuel injection is that you're taking some antiquated technology that's over a 100 years old (internal combustion engine) and marrying it up with something that's to precise (a computer).

 

RonD,
Ijust read this post about check engine light and the gas cap, etc. I have a 1997 2.3L 4cyl that has had that problem for the past 15 years at least. No one in my area has been able to figure out whats going on and all have told me not to worry about it. It seems as though it only comes on when the outside temperature is above 32 degrees. Any advice?

 

Welcome to the forum

Yes, unless you have to pass emissions test in your area this code is not a big concern

Get a wet rag and short hose
Remove gas cap and put hose in the opening and wrap rag around it to seal the opening
Blow into the hose and see if tank will hold pressure, DO NOT use an air compressor for this, you WILL blow off fittings, lung pressure only, which is 2psi max

A Young helper with good lungs is helpful, if it doesn't hold pressure, because you can then listen for where air is leaking out while he/she blows into the hose
Filler neck?
Top of tank?
Engine bay hoses?

If tank does hold pressure then its likely that the computer itself is the problem, its EVAP pressure circuit has failed, maybe it's the pressure sensor but thats a different code usually, a "circuit" code