Engine light + "Restricted Performance" warning in cold temperatures

I believe I had this happen once last year on a particularly cold morning. This year, I've had it twice now. Once when it dipped into the 20s overnight, but again today when it only got down to just below freezing over night.

I don't notice any change in the way the truck drives, and in every instance the light and warning message have gone away after 3 engine cycles.

Ignore it? Or worth checking out?

The codes? If it’s p2118-19 it’s Likely a dirty throttle body. Do a really good job of cleaning (it doesn’t take much to make that code trip). I also got a code for the MAP sensor (sits right behind the throttle body).

my money it’s this

scott schmerge said:

The codes? If it’s p2118-19 it’s Likely a dirty throttle body. Do a really good job of cleaning (it doesn’t take much to make that code trip). I also got a code for the MAP sensor (sits right behind the throttle body).

my money it’s this

Click to expand...

Unfortunately, I don't have a GAP tool to provide more info. Wondering whether this is worth going into the dealership for.

hatch said:

Unfortunately, I don't have a GAP tool to provide more info. Wondering whether this is worth going into the dealership for.

Click to expand...

go to autozone and pull codes. Free

You can even go ahead and clean your throttle body without pulling codes. My guess is it’s got some carbon buildup. If it stops going into restricted performance, that’s your cause. Make sure to get around the pivots on the butterfly

scott schmerge said:

go to autozone and pull codes. Free

You can even go ahead and clean your throttle body without pulling codes. My guess is it’s got some carbon buildup. If it stops going into restricted performance, that’s your cause. Make sure to get around the pivots on the butterfly

Click to expand...

Had no idea you could pull codes at AutoZone for free. Will have to check that out.

And the carbon buildup would make sense re: it tripping the code/warning when temps drop?

hatch said:

Had no idea you could pull codes at AutoZone for free. Will have to check that out.

And the carbon buildup would make sense re: it tripping the code/warning when temps drop?

Click to expand...

Yes, that would make sense. Air is more dense when it’s cold, and your throttle body is slightly smaller in cold temps. Even the slightest variation with a little carbon buildup could cause.

Your vehicle is from Florida?

ktm525 said:

Your vehicle is from Florida?

Click to expand...

Nope. Where'd that idea come from?

Just a comment from up where cold is a norm. The heater in my 3 is good for about -35F on the highway as is the rest of the vehicle. Even by Made in USA pickup standards, that is good and it starts etc.

While a dirty MAP is probably the problem, check how the piping between the air filter, the MAP and into the engine is connected.

I discovered that the dealer service guys were checking the air filter by just undoing the air filter lid screws and then tipping the lid up to peak inside.

This was effective, but what also happened was the piping downstream of the air filter that was torqued upwards, tended to open up at those rubber seal joints and hence leak air. Effectively, non filtered air was entering the engine downstream of the MAP and that messed up the air metering.

For me, there were no lights, but the hint was that the fuel mileage went bad by about two to three miles per gallon.