Hey guys could a bad plugged cat cause my truck to stall? 06 f150 fx4. Changed plugs and cops last week took it for a ride and still runs like crap and now is stalling out when coming to a stop or slowing down. It threw bank 2 bad cat code before I got the plugs changed. When in gear idling im sitting at about 200 rpms.

 

I also changed the fuel filter... still no good

 

Have you tried cleaning the maf and throttle body?

 

Welcome to the club. I wish I could help, but I'm in the same boat.

 

No i havent... The shop owner said he would clean the throttle body when i brought it in to get the cats installed...

 

And to 88 racing;

Yes. I've done both multiple times.

Plugs changed
Throttle body changed along with new Throttle position sensor
I crawled under it yesterday and looked at the Fuel Pump driver module. It didn't look all that bad and it wasn't cracked. I didn't remove it for fear of damage and not having another close at hand.

 

When you get on it and tack up the rpms while driving does it feel like your hitting a rev limiter?

 

Cleaned MAF still running bad... I'm still thinking the CAT is plugged...Ordered some High Flows should be in this week

 

If it threw a cat code (P0420/P0430?) it's probably plugged.

 

No. If your truck has a fouled cat, I'd say somthing else is wrong with it too.

 

I "think" the bad plugs fouled the cats. I dunno but i really dislike this truck right now.

 

What brand of plugs did you put in?

 

Motorcraft

 

If I hammer on it it doesn't even reallyaccelerate. Just sounds like I'm hitting the rev limiter. Then it will want to stall when coming to a stop. If i keep on the gas and the rpms up the check engine light will flash and the truck will shake.

 

Have you checked the injectors? A leaky injector could be flooding a cylinder.