I have a 2003 heritage edition f150 with the 5.4 I pulled the cats and used mil
Eliminators I consistently throw a code on one side only I have third multiple
sensors even the factory one directly from Ford still no luck. The code was originally on bank
One I switched the sensors from driver to passenger which moved the code to bank two now I put in a Ford sensor from Ford same as the one I took out and now am throwing codes on bank one and two the codes are po420 po430 I am at a loss I did this in two of my other vehicles with no issues but this truck is causing me grief any help would be appreciated in justbnot sure why the code was not there then I put in a brand new sensor and it thows a code I have tried multiple sensors no luck pleas please help also no issues with driving the truck other then the code please help thank you.

 

Just curios what's a mil eliminator? And I believe only the 04 in the 10th gen body style is a heritage, correct me if I'm wrong.

 

Malfunction Indicator Light eliminator. it goes between the o2 sensor and its plug in to read it correct if your cats are out. so it doesnt throw a SES light

 

Yes jaydee is correct I also thought it was an 04 but after checking the Vin number
Turns out it's an 03 I have been told many different things lol nice truck but yes it has the older body style which is why I assumed it was an 03

 

Also I have my exhaust done after cats all new exhaust except for the. I'd pipe where the sensors are located could that effect sensors as well.

 

03 heritage edition is the 100th annivarsy of Ford it was a special editon available in a limited number form ford. On the MIL's the new pcm strategy codes do not like them and it will see right thru the o2. Just get a tuner to turn the rear o2's off.

 

I asked a salesman at an auto store if you could do that he said he didn't think so any known brands that this would work with?

 

They make a tuner for our gen truck that will turn rear o2 off? I didn't think that option was available for this gen

 

I have some mil eliminatirs out in the garage, I was going to use them on the Harley and still might if I start having problems with getting inspected, I had my tuner turn off my rear O2's so I don't throw a check engin light, but it still reads not ready when you get it inspected... oh well..


Are you using these eliminators when you plug in the new sensors? Because I was thinking maybe one of them are bad? Also, have you tried the spark plug non foulers? Just throwing that out there. I've never done it myself but those plus the eliminators may work, or some concoction of the sort.

 

Harley9703 what kind of tuner do you have I just want it so I don't have the mil light