mountain Horror Story

We just came back from a wonderful 5 day vacation to Colorado.  With one scarey problem that caused my wife to say never again I guess we will never take this TV over 10,000 feet again!  We went thru Estes & up into the RMNP, after climbing up past the bathrooms & getting about 2 miles the truck just started idling very rough so I pulled over to check it out. Before I could even get it in park the check engine light started flashing then it died. After trying 4 times it restarted & ran ok but the check engine light stayed on steady. All I could think was good now it has thrown a code & when I get back to work Wednesday I will put it on the computer. We tried going on up & it died again, but then it would not even crank{ Damn Computers} We then coasted backwards{Very Scarey} to a turn out & I again got under the hood & checked everything I could. After about 10 minutes it still wouldn"t fire so I cycled the key about 10 times & got it to run. As we were retreating down the mountain the check engine light went out. We drove 500 miles after that with no incident, until we were about 65 miles from home and it just died & restarted itself going down the hiway about 60 mph. The silly thing never gets over 13 mpg empty but this whole trip it amazed us by averaging over 15 mpg!
I am now glad DW & DD did not want to pull the TT. The other good news is we had a great time in Colorado enjoying the cool weather & all the sites Oh & now DW even thinks 39,000 miles is the time to trade for a Duramax!  Wish me luck!

That is scary. Glad you made it o.k. Let us know what code was set and the problem.

Wow, too bad it took something like that to get what you really want anyway!  Good luck.  Dad just got back from a western US/Canada whirlwind tour with his 07 DMAX pulling his 34' 5er and nary a problem.  He did blow a trailer tire in Oklahoma on the way back, but no damage to the trailer.  But the truck performed great.  He's happy.

Corvette,
 
  Your problem sounds like a problem I had with my 2004 Chevy 2500 6.0. I Was making a very uneventful trip to Lake Tahoe, uneventful until I got to the top of the mountain. When I reached the top my truck died, and like yours restarted again. I drove another 2 or 3 miles and it died again, and then restarted again. Well to make a long story short it was the fuel pump. The dealer did some investigating for me and found out that the fule pumps have been failing on that particular year truck, with that particular motor when driven in high elevations. Mine was under warranty at the time, so I'm not sure whetehr it was a warranty issue or a recall issue. I would head to your local dealer and ask them if they have info on the fuel pumps failing in that truck. Hopefully it will be a easy fix for you...

Steve

Could be an altitude related problem - the Check Engine light is often an indication of an emissions control failure. Should be a code in any case to give more info.

That ride up to Estes and RMNP is certainly not one for the faint hearted - or for an ailing vehicle.  That new Duramax ought to handle it nicely, though. 

I had a similar experience with my Dodge.  We had towed our trailer through
Colorado over 11000 ft with no problems, but the next day just driving the pickup by itself, at 8500 ft, I got a check engine light.  I took it to the Dodge dealer and they said it was the MAP sensor.  They didn't replace it, just reset the error code.  I haven't had a recurrence since.

I agree, As you go UP the mountain air gets thinner, there is less and less O2 in the air, You may have reached a piont where the engine could not suck enough air to fully burn the fuel, This would have set a "Rich run" code.  That is the bad news.

Now the good news: There may be a TSB on this, check with a dealer, (One half way (or more) up the mountain if you can) and it may be something that either they, or you, can easily fix.. Could be as simple as installing a new air filter to fix it.

Then on the othe hand...... (I am an optimist after all) could be serious.

Thanks for all the great ideas!  I put it on the computer today and only got a code 300 which is just an intermittant multiple misfire. As this happened again down here in the flatlands of Nebraska I am thinking it is the fuel pump. The 04 6.0 is the 1st. or 2nd. year they used this variable speed pump with no pressure regulator or external fuel filter. I have friends with the 02 6.0 & they always get better mileage than mine has.  I told the family we should have driven my old 94 Silverado as it has been up that road many times since new & has always made it!  The only Colorado trip it almost didn't make it was when we were going down Phantom Canyon Road south of Victor going to Canon City & met a 1 ton dually with a 36 ft. trailer at a very narrow spot. We had to fold all mirrors in & put the right tires clear out on the edge & he scraped his trailer on the side hill.  My wife says she still has a high pucker factor every time she thinks about opening the right door to check how close we actually were & seeing straight down!  I can't believe she wouldn't let me drive down that road this year!

82corvette said:

We just came back from a wonderful 5 day vacation to Colorado.  With one scarey problem that caused my wife to say never again I guess we will never take this TV over 10,000 feet again!  We went thru Estes & up into the RMNP, after climbing up past the bathrooms & getting about 2 miles the truck just started idling very rough so I pulled over to check it out...

Click to expand...

If by "past the bathrooms" you mean the overlook that's about halfway up -- that's where my wife got out of the car and refused to go any further.  She told me to go on up and pick her up on the way back down.  Took me about 15 minutes to talk her into going on.  Then she laid the passenger seat all the way back and stared at the ceiling the rest of the way.  Now she says, "Never again."  She didn't mind the ride up to Leadville, though...

Sounds like it might be a good idea to upgrade to a Duramax diesel in a new tow vehicle. I didn't realize the GM gassers had that type of track record.