What makes the Check Engine light come on? Mine just popped on this morning at an odd mileage 86426. I could see it coming on at a nice round number to get you to take your truck in for a check up, but this is strange. The truck is running great. So what should I look for, and how do I reset this light?

THANKS
dave

 

The check engine light can come on for any number of reasons including a loose filler cap. The owner's manual says that if it comes on for 3 cold engine starts, then cylcles off, there is no need to take it in for service. This happened to me and they said it was two bad O2 sensors (big bucks at the dealer - should've done myself).

------------------
------------------------
1998 Expedition EB
- 4x4
- LLS (4 corner)
- Premium MACH Sound System w/6-CD changer
MODS
None yet (But I wanna be like you guys)
------------------------

 

Mine also just came on. I only have 5400 miles however.
dbunch5 is right about the 3 cycles. Leaving work today will be 3. Hope the light goes out. I checked the gas cap and it was fine. Owners manual said it could also be bad gas. If not, I'm obviously still under warranty.

------------------
2001 F150 XLT SC SPORT 4X4 FLARESIDE
* Black
* 4.6
* Auto
* awesome factory 10 spoke 17" wheels
* "MAN"ual shift 4x4
* 3.55 Limited slip
* Captains chairs W/console
* Factory tube steps
* Slider
* FORD bedliner

 

My light came on the two seconds after I
drove it off the lot. It had 73,097 miles on
it. It would go off, then come back on, then
go back off, etc.... It did this for a month
while I tried the gas cap, better gas, and
numerous other things. I finally caught it
on long enough to get it back to the dealer.
They had it fixed in a day. It was the EGR
valve? I think that is what it was called.
I have noticed on most posts on this site that the most common cause is the O2
sensor(s) that are located both before and after the cat. Hope this helps. I feel your
pain.

 

Mine came on real close to 100K. Mine was a fuel pressure regulator and a fuel vapor sensor. Something like that. I assumed it was an O2 senosor. I was wrong. What sucks about all this is you have to take it to a dealer. They hook the truck up to a computer to get the trouble codes. It all cost me around $400. Gotta love OBDII.

------------------
1997 F-150 XL, 4.2L 5spd
Mods: 16x8 Centerline wheels, 285/60/16 Goodyear Eagle GT IIs, Flowmaster, tint, alarm, billet grilles, clear corners, 2001 Lightning Tails, carpet, Kenwood CD w/Infinity speakers, 60/40 seats, and a 5hp "Ford Racing" sticker on the back window.