the guy i bought my truck from had the 2 catalytic converters cut off only on the drivers side, with a straight pipe replacing it. it ran really rich and had to run premium in it, but still ran pretty good until i had to replace the computer, which was probably because it couldn't adjust to the cats being off. so i went and replaced the catalytic converters and oxygen sensors on that side. it runs good until i really get on it. it would shift fine and accelerate and then it would bog down with rpms still increasing. i took it to the shop and they watched all the o2 sensors and the one on the drivers side after the cats was falling and causing the truck to run lean. all the others on the graph were moving up in down indicating they are working except that one. these are brand new oxygen sensors could it be i got a bad on or is there something else it could be? please help me out

 

the converter may not be up to par with the ford ones, when i replaced mine on my truck with high flow's my CEL stayed on with the catalyst codes, then i did the GOTTS 02 mod and CEL hasnt came on since. may give that a try?

what sensors did you buy?

 

well i bought oem direct bolt up catalytic converters (not high flow ones)/ and bought bosch o2 sensors just for the drivers side since thats the side i put the new cats on

 

hmmm..everything should be good then...and your sure they are threaded all the way down, and plugged in all the way?

 

yea im about possitive, they are plugged in pretty snug and i know they are plugged in. its only the back one that was showing bad. could it be that they gave me a bad sensor?

 

I heard of someone on the forum that had an 02 problem I think on the passenger side and he found some wires rubbed through around the firewall/bell housing area. give it a good look see-maybe. Ilike simple and cheep first!

 

yea i will look at it, but the thing is that it was running fine before i had to replace the pcm in it and thats when all the troubles came

 

its very possible that you could have gotten a bad sensor. its electrical and could have been damaged during shipping

 

Are you sure the cats you didn't replace are good?

 

well im going to assume so im not a hundred percent possible, just the guys at autolab diagnosed it and told me that that back o2 sensor was not working

 

It kinda sounds like a back pressure in the exhaust issue. Those cats could be jacked up. This is a little risky, I did it on a toyota i have, back off the bolts where the pipe connects to the manifold on that side so you have an exhaust leak, then take it for a SHORT trial run. If it rruns much better then the cats are pluged up. This will set a po174 or something like that, but at least you'll know if it's the cats.
Good luck

 

or if you drive about 30 minutes and that son of a gun is glowing red, you got bad converters