I have a 97 f150 4.6l what are these codes that keep coming up. I believe it is egr valve and miss fire in 4 cylinder.. But I just had that stuff replaced 1 1/2 years ago.. Any help what I should check now.. The egr vavle looks great. No gumm up or anything.?

thank you

 

Those codes are for cylinder 3 and 4 misfire. When is the last time the plugs were changed? You might also have a bad coil.

 

I would do what Stang told you first, and if that doesn't work...check the connections to your fuel injectors. Also, MAKE SURE YOU REPLACE WITH ONLY OEM PARTS!

 

^^very good point ...

make sure you use Motorcraft ONLY!

 

I changed the plugs and wires a year 1/2 ago. And im not sure what egr valve i used... If you do not use oem do they not work right with the car or something? I am completly clueless about this, but i know the shop wants like 500 dollars to do the repair and know thats a rip off

 

Yea these motors are just really picky on what plugs you use (especially the triton motors), so it's always best just to stick with motorcraft. Yea, 500 dollars is too much, try getting different price quotes. Have you ever thought about doing them yourself. Otto (another member on here) has a great write-up on how to switch them out https://www.f150forum.com/f72/97-03-...89/#post877200

 

Misfire makes me believe the problem is the COP (maybe more than one). The COPs are known problems with Ford.

 

Thank you for the reply. So now I got the misfire in 4 cylinder code gone. For the other.... I changed the egr valve, changed the hoses going to the dpfe sensor. The dpfe sensor looks fine. But should I change that now .. Or where do I go from here? The vehicle does not idle rough at all. honestly the only thing is that is gets horrible gas mileage....What should I do next..? I need to pass emissions asap. can I just clear the codes than run it up to the emissions place will it pass?

 

Change your plugs! Motorcraft!

If its getting bad gas mileage then that would be my first thing I would check.

 

check to see if you are getting water or coolant into the spark plug holes. there is a heater hose that runs above these 2 cylinders and they have been known to leak and cause this problem. if this has been recurring or has lasted a while i would think about replacing the coils . if you do another tune up switch the position of the coils with ones that don't miss now and see if the miss follows the coil.