2013 F150, 3.5 ecoboost. Engine light came on and shows code P0340, which says catalyst system efficiency below threshold( bank 2).
Is it safe to say its the catalytic converter?
Is there anything else that could cause that problem?
What in the world is bank 2?
Thank you for your time.

 

Bank 2 refers to the side of the engine for cylinders 4,5,6. In your case it should be the drivers side.

the p0420 code for bank 2 is saying that the converter on the drivers side is not operating within the expected parameters. Meaning, the oxygen content coming out of the converter is not as expected and it is operating with a lower than acceptable efficiency.

to verify, you can warm the engine up and then run at 2500 rpm for 1 minute. Check the temperature with an IR thermometer immediately before and after the converter. If the converter is hotter on the exit side, it’s working. If it’s the same on the inlet and outlet it isn’t doing anything. And if it’s hotter on the inlet, then it’s plugged. You should see a few hundred degree rise across the converter if it’s working right.

 

I believe a p0340 code is a problme with the cam shaft sensor.... which is giving you bad readings at the CAT..

 

Thank you for the correction. I clearly misread his post. I have p0420 on the brain from another project I’m working on.

the info I gave is pertinent to p0420 code for catalyst efficiency.

problems with a camshaft position can definitely be detrimental to converter longevity.

p0340 is for the camshaft position sensor
p0420 is for the catalyst efficiency below threshold.

hence my confusion.

 

Is that the problem with the valve timing advance? The one for which some recommend a kit that basically disables the variable timing?

 

That sounds like a Camshaft Position Sensor code being thrown. I've gotten that in a different vehicle and just changed the sensor, seemed to clear it up.

 

Hey guys.
Looks like everyone is having trouble with the code and its all my fault. I had one of those senior moments and turned the 3 and the 4 around.
The actual code is P0430. I triple checked this time. Please accept my sincere apology for screwing up.
Thank you and everyone have a very MERRY CHRISTMAS.

 

P0430 is for catalyst efficiency below threshold on bank 2.

see my first post.

 

Ah. Change the downstream O2 Sensor, maybe get some defoulers as well before you put a new one on. Bank 2 is the Driver's Side and the problem is probably the downstream sensor, which is after the catalytic converter. Defoulers pull the O2 sensors out of the exhaust gas flow just slightly, they are inexpensive. Click here for Walmart listing. I've used them on several vehicles with great results, especially for older vehicles with higher mileage.

I hear a lot of debate about O2 sensors and other drivers just letting them go without changing them. In my opinion they should be changed when they go bad. They regulate the fuel mixture in the combustion chamber and can lead to other issues if they're not changed. When your vehicle gets a trouble code that points to the O2 sensor, it will run with a default setting and the PCM will not adjust the fuel mixture as effectively. Which can lead to poor economy, poor idle, low power, wasted fuel, black smoke, dirty valves, dirty fuel injector ports, ect...

Minimum, change the sensor, it's a cheap fix.

 

Sensors don’t go bad very often. They can, but it’s rare. Converters are the same. Both are pretty reliable.

check the temperatures on the converter like I suggested before spending Any money on parts.

 

That is the plan. Check everything out first, then proceed from there.

 

I just got a truck with a bad converter. The ceramic media inside had broken loose and was plugging the outlet. The symptoms were reduced power and codes for limited throttle body actuation and torque production.

the converter was 200 degrees colder on the outlet than the inlet which in conjunction with the codes was a pretty clear indicator of a plugged cat. (The temperature readings alone would condemn it).

I dropped the cat to address the problem and that’s when I saw the ceramic media already falling out of the converter. There were indications that the media had made its way into the muffler, but it was clear of any obstruction so I didn’t replace it.

When I removed the oxygen sensor, it was badly seized. I had soaked it for two days In penetrating oil and I heated the sensor bung for with a propane torch for several minutes. Long enough to get it a dull red. With an offset sensor wrench and an impact gun I was able to get the sensor out, but it pulled the threads on both the sensor and the bung. I was able to save the bung with a thread tap, but the sensor - which worked fine - was destroyed.

I say all of this to 1: give you fair warning that they don’t always like to come loose, and 2: give you a list of tools to consider and a plan of attack to remove the old sensor.

if you need or want to replace the converter, I’d recommend just getting a new sensor and save the hassle of removing the old one. If you aren’t replacing the converter, but need to remove the sensor, be prepared for galled threads on the sensor bung.

Destroyed threads.

Threads after spending 4 minutes going back and forth with a thread tap and an impact. Restored the threads, but it was touch and go whether it was going to work.

 

I was wondering about that. I had already decided if the converter was bad to put in new O2 sensors. If the sensors are that tight I may just replace the converter any way. We'll see probably this afternoon.
Thank you.

 

99% of the time the converter is bad .. For whatever reason the first gen ecoboost like to eat the driver side cat. For ever 1 pass side i replace, I do 10 driver side.... If you live in a state that requires emissions it will need a cat. IF not, just drive it. The P0420/430 doen't hurt anything on the engine. Get oem cat and o2 sensors.. Aftermarket stuff is much cheaper, but junk most times.. Misfires cause cat failure. Do spark plugs every 60k if you work the truck, or every 90k if you dont. Coil pack can be an issues on those as well. If you still have a misfire after new oem plugs gap to the 0.030 then replace the coil on that cylinder. Get all misfire issues correct before relacing the cat. Ok, enough BS, now I need to go out side get to work.