Hey hey...

New to the site so don't beat me up too bad. I just bought a 2006 F150 Supercab 4 x 2, 4.6, truck has 129K. Drove it with no problems, Last weekend it died a few time while coming to a stop. I have no "check engine" light on, and I notice the rmp were about 450 to 600. Since then I have not had a problem but I know something has to be addressed? Is this most likely an IAC issue? Can it be cleaned or replaced? What's the best thing to clean it with? I've read to clean your throttle body as well, how do you do this? What about the EGR valve, replace that as well?

Thanks in advance for your help.

 

The things I do with any new used vehicle...

These are the easier and relatively cheap things:

• Replace the PCV Valve
• Replace the air filter
• Clean the IAC (make sure everything moves easily)
• Clean the MAF (carefully)
• Replace the fuel filter
• Replace the plugs (read the threads about soaking them first so you don't break them) - time consuming but not hard if you're careful.
• Make sure the COPs connectors are all plugged in securely
• Fuel Injector Cleaner - minimal improvement in my experience, but some swear by it
• Check the belt - won't make it run better but if it's in poor shape it needs replacing

More time consuming:

• Replace O2 sensors - can make a big difference but slightly on the expensive side
• Clean the throttle body, especially the EGR ports \ tubes
• Pull the injectors and have them ultrasonic'd (they're expensive to replace)

I know this sounds like a lot, but unless you have a full maintenance record of the vehicle's past, servicing these items soon will go a long way towards ensuring a well-running vehicle.


If it's still idling poorly after this, then start troubleshooting...

Just my .02.

 

Seware has it correct.

I'd start with the MAF, Throttle Body (including all ports), PCV and Fuel Filter.

Then move on to plugs if that didn't fix it.

If it was a COP or O2 it would most likely give you a code right away (CEL) but not always.

The other items like Belt (and tensioner) and air filter fall under normal replacement.

 

I have no experience with a COP throwing a code, but I (stupidly) ran my original O2 sensors for almost 10 years. They never threw a code (meaning they were still reading "in range" maybe?) but as soon as I replaced them my mileage went up and it ran a whole lot smoother than it had been near their end. Do they die slowly and throw codes at death's door maybe? Somebody smarter than me can explain. My .02 is based solely on my experience.

Good luck raider.

 

The 06 does not have an IAC, it has an electronic throttle.

Plugs don't have to be soaked with a 4.6, they are standard 1 piece plugs with threads and no ground sleeve.

 

Thanks for the correction glc. I'm keeping my 98 until it rusts to pieces... so I wasn't aware on the IAC.

However, I still soak my plugs on my 98 4.6, because I broke one early on in its life... a leaky heater hose had dripped down around the boot on #4 and corroded the whole thing. Snapped right off when I tried to pull it. That style of plug isn't so hard to get out as them fancy schmancy new ones but can still benefit from some penetrating oil.

 

Ran my first set of O2 for 210K miles. I had no issues but I saw lots of post for better mileage. Replaced all 4 and saw NO CHANGE. Giant waste of money. It might be the older model O2 slowly go bad, but it didn't help me.

 

Great info guys, Thanks! So my 06 has no IAC? I have done the fuel filter, belts, plugs, wires, tranny fluid and torque converter. I installed a s&b cold air intake but did not clean the Airflow sensor? Do you clean that with a special cleaner? What about the throttle body, what's the best product?

 

MAF cleaner and throttle body cleaner.......

You don't have wires, you have a coil on top of each plug.

 

Replacing the rear O2's is ALWAYS a waste of money unless they actually go bad. They don't control anything that affects the way it runs, all they do is report on cat efficiency for emission control purposes.

 

I don't know enough to disagree with you glc, but it was a noticeable difference in mileage (~1.3 mpg) and how it ran after changing O2s... can you explain? coincidence? I'm not trying to be cheeky... just telling you what I experienced.

 

I'm only talking about the rears - the front O2's do affect the way it runs.

 

oops....yeah no wires...taking apart tonight...Thanks for everyones help.

 

UPDATE....Light came on today...first time I used the A/C in the truck 97 degrees today....

 

CEL? What's the code?