Why does my Check engine light come on when I get above the 5000 ft elevation level?

Question

I have a 2003 Dodge Ram 1500 Hemi and when I am traveling and I get to a place where the elevation is 5000 Feet and above my check engine light comes on. The dealer says they are unable to get the error code reading because when the light goes out the error code is erased. The light will stay on for a couple of days if I keep my truck above the 5000 ft level but if I get below the 5000 ft level and shut my truck of for 30 min. to 1 hour the light goes off so I have no way of getting it to the dealer while the light is on. Does any one know of something I can replace on my own that might fix this problem

Answer 1

oxygen sensor

Answer 2

First if the light comes on the car will have a code stored. I find it hard to belive that the dealer can't find it. Second my guess would be that since the air has less oxygen above 5000 feet that would be the cause. However the next time you plan a trip to some place above 5000 feet why not call a dealer in that area and have them check it while the light is on?

Answer 3

Most likely its the ecu that is not adjusting properly for the elevation chages.
As you climb in elevation, the fuel/air mixture will get rich because the oxygen levels go down. A properly working ecu or engine computer wull usually adjust this automatically and lean out the mixture.

You are probably getting a too rich mixture causing the exhaust to trigger the oxygen sensor.

The oxygen sensor can be replaced as a first step. Then see if the check engine light comes on. If it still does, take it to a shop where they can read your cars trouble codes. This will pinpoint exactly what is triggering the check engine light to come on.

Answer 4

Do you make this trip often? Get yourself one of those computer programmers, like BullyDog's or something. What's happening is that the air is thinning out, and making your truck run rich (more fuel than air). A controller will let you make all kinds of changes, and should let you play with the fuel curve so that this doesn't happen again.

This is a guess on the internet though...check into some Dodge forums and find out about anyone else having this problem. Maybe there's a Denver chapter in a Dodge Ram club, and they can let you know what's happening.

Answer 5

It's not the O2 sensor. it's probably the absolute barometric pressure sensor. It should store a code. It's a software thing that happens to a lot of vehicles when they gain altitude and the temperature drops. You can get an OBDII scanner for about $70 and check it while tghe light's still on sometime to be sure.

Answer 6

hello,
It would be most likely an altitude problem. Thinner air big engine slower cooling. if your using only water as a coolant, then consider some "real coolant" like Etheline glycol anti-freeze. Prestone might Be available in America? That would be my reasoning behind the altitude sickness.

Answer 7

My recommendation is that the next auto parts store you go past, you stop in and ask if they can run a system scan on your car to see what the code is. My guess is that with all the hills you were probably going through that the transmission overheated.

Answer 8

The O2 sensor is responding to the atmosphere being low in oxygen at that elevation.

Answer 9

i would suspect the o2 sensor as well , also see if the Dodge dealers in Denver have anything to say about this , good luck

Answer 10

the higher you go, the thinner the air gets. therefore making it harder for the truck to breath. my Father in law has the same kinda truck. the dealer told him just what i told you. sucks they do that. they are pretty freakin sweet trucks!