System lean codes.

My daily driver turned on the money light. I've never had a check engine light on (incredibly) in my 99 Navigator, so I was kind of excited to get in there. Probably makes me weird.

It was setting lean codes on both banks, with crazy high fuel trims. I found all of the pcv elbows collapsed and some degraded lines.

I checked the trims after the repair and everything was in proper order.
I decided to not clear the codes or keep alive memory, and see how long before the pcm realised the truck was fixed.

More than a month later, she's finally happy!

Noah wrote: my 99 Navigator

More than a month later, she's finally happy!

That's a ford for ya :woohoo:

I wonder if a newer OBD 2 vehicle would have seen the correction sooner.

Noah wrote: I wonder if a newer OBD 2 vehicle would have seen the correction sooner.

Maybe? I feel like newer models will turn the light out sooner, but will keep the codes in history just as long.

Always been curious to try this, but no customers I know would put up with having the light on for a month...