Changed the fuel filter on a 2001 Ranger Edge 4.0L and the 'check engine' light came on 40 or 50 miles later. I disconnected the battery to reset the computer and the light stayed off for another 10 miles or so then came back on.

I did notice that I could not distinguish between the two connections on the inlet/return side of the new filter as I could on the old filter. They were asymmetrically located on the old one with one on the side and one in the center but the new one had connections that were equally spaced and identical. Could it be that swapping the two could allow the truck to run well but trip the check engine light?

The only other things that were out of the ordinary were that the black plastic portion on one of the fuel line connectors was cracked below the clip but it didn't seem to affect the tightness of the connection, and we did put a K&N air filter in 3 or 4 weeks earlier.

Any ideas?

 

Rather than guessing at the cuase of the CEL I would pull the codes. Some parts stores (autozone) will pull them for free.

 

If the K&N filter was over oiled you might have contaminated your MAF sensor or various other things.

I did that in my v8 supercharged Tbird(was big PITA to fix it)

Rand

 

If it does come up with the MAF code, it's not hard to clean, go to mechanicmatt.com.

 

>If it does come up with the MAF code, it's not hard to
>clean, go to mechanicmatt.com.


Right I should have clarified Its easy to clean
it was a POS to fix my tbird

since it had a custom superchanger installed on it too
and the first owner of it should have been shot

Rand