I've taken 3 - 2,000 mile round-trip road trips and the truck rode well and smooth. Nothing but a drink every 300-400 miles.

This past weekend, I took a little 200 hop from 5280ft elev. to 11000ft elev, filled up, and the engine light came on. It stayed off when we went out the next morning. Before heading home, though, we filled up again and the engine light came on.

I haven't driven it yet, but when I check on it, it stays on. I've scheduled time with mechanic.

Anyone else have this problem? Both times, I checked the gas cap and made sure it fit correctly and clicked.

 

When you "filled up again", what elevation did you fill up at? Were you back at 5,000 feet? Just thinking that the light may be caused by a misfire or some parameter being out of bounds due to the thin air... or perhaps bad gas which might not be a big deal at lower elevations, but became more of a problem with the thin air.

However, if you refilled at a lower elevation and still got the light, then my theory goes out the window.

 

I filled up both times at the higher elevation.

 

Then, if it were me, I would just clear the code (either by using a OBD tool if you have one or I think performing a "hard reset" should do it) and continue on my way. If the check engine light comes on again during your "normal" driving conditions, then I would take it into the shop.

Perhaps a LR tech can chime in and give their $0.02, but if you're dealing with those high elevations, I would bet it's just an air/fuel ratio problem or bad gas (perhaps too much ethanol) that was exacerbated by the thin air.

 

There is a TSB regarding high elevations and issues, I know the tank seal is also proven to be an issue on that. I wouldn't worry too much about the 2nd though, unless you can smell gas. I think this is the TSB I was thinking of..

1. 
   
   LTB00429NAS3 - Poor Engine Performance At High Altitude

 

If you search this forum and a few others, I'm 95% certain this issue has been reported before; another person operating at high elevations.

 

Started truck, engine light went off, de-iluminated; drove around, about 30 random miles, and the engine light didn't come back on. Can't say exactly what was wrong, but I'm thinking elevation played a part in this.

 

Basically, sometimes, with the LR3....weird $hit happens!

I was coming back from the Yukon Territory last March and we saw -17F overnight. Although I had the truck plugged in, I got a CEL the first morning. I figure the vehicle was just "mad at me" for being in the cold and I cleared all faults with my IIDTool; never saw it again.