01 f150 5.4. I can barely pull a hill from stopped. No codes but I know something. I keep rearing take the rear cat off. My truck has a small cat or something then direct down hill is a bigger one I'm familiar with. Is that the rear one I am reading about

 

Take a look at your Catalytic after running your engine until exhaust is hot, then take a look at it in the dark, if it's plugged there is a good chance it'll glow red, if not then it's flowing good.

 

If you want to test your cats, get a pressure tester that you can screw into the downstream o2 sensor bungs. One the truck is up to temp have somebody hit the throttle like 5 times real quick and if it spikes up over 1.5 you need new cats.

 

to be honest man, i would replace your plugs and wires. my truck was acting totally stupid with that type of stuff like power loss and stuff, no engine codes. now its running like it should! and it was only like 80 bucks for everything, i have a 6-7 motorcraft spark plugs i could send you that i found after doing the plugs (dangit!)

 

Thanks for the cat tips.
I changed all plugs a few months ago.
I have a hieli coil on #7 and they put different coil pack on. So I have 6 motor craft and two duralast. I don't like it but its all I got. Send the plugs if u want though

 

Mixing plugs ain't good!!

 

I agree. It's the coil packs that r mixed. When I can find $350 ill put 8 coils& plugs in it.
I checked the cat tonite and the drivers side was glowing.

 

I'd say that particular one is clogged. Might want to look into changing it or running straight pipe vice re-installing a Catylitic if that's cool with your emission rules over there.

 

No emissions over here. So I read all the time about deleting rear cat. I have two peices that look like a catalytic converter. It goes-from engine to back- o2-little cat-long cat-o2. The long one is the rear I guess. Thank you for ur help

 

Yah our trucks have 4, the two front ones are also called resonaters and there actually not that restrictive, the back two are the most restrictive so youll just want to take those out an replace with straight pipe. I did that and it really helped the flow in my exhaust, no cel and i even passed smog without the back two...and i live in ca!