Broke Down on Vacation

[MEdlin]

Help...

My 1994 Suburban (6.5 TD, 178,000 miles) quit while driving down the highway. Just like someone turned it off. I was able to shift into Neutral and hit the key while moving and it started back up. Other times, I just had to pump the fuel pedal and it started back up. This morinig I started the truck at the campground and it ran very rough between 1500 and 2000 rpm while in park. I also noticed a little bit of black smoke. Sounded like a gasser that was missing about 3 plugs.

I recently replaced fuel lift pump, oil pressure switch, fuel filter, cleaned fuel pump relay, and tightened and cleaned all gounds and all connectors across back of engine. I'm also running with the Stanadyne additive in the fuel. I drove it for 1300 miles straight from Kentucky to Golden Colorado. The truck never drew a long breath! It began acting up after driving through the Rocky Mountain park. There are no DTCs or Service Engine Soon lights. I have 1/2 tank of fuel, so I don't suspect bad fuel. I drove it about 10 miles this morning with no trouble.

Any ideas ? Could this be a problem with altitude? :confused:

[Barry Nave]

When a FSD/pmd starts going out there will be no TDC. Do you know the history on your fsd/pmd?
Pull the fuel filter and take a good look at it and inside the fuel bowl.
Had this happen once with my pmd mounted on a fsd cooler. The next morning truck ran fine till the heat of the day and letting the truck cool down would run for awhile.
Just keep getting wourse though.
Is your pmd still on the pump? Are you still running the gray turbo cover on the truck?
If your turbo cover is still on, then pulling this of will help keep the pump cooler.
Keeping the tank as full of fuel will also help the pump stay cooler.
Getting the fuel down to 1/2 a tank,the fuel will start heating up as the fuel will alway be returning back to the tank as the Eng. gets hot through out the day.
Are you towing?
Are the temp. staying under 200*
There can always be alot of ifs so as much as we can learn about your truck, like what all has been done to the Eng sence you have owened it the more we will know. Give us as much history as you can and we will be able to help.
Pump change out, when? for at some time the pump would of had to been changed at some point in time. To many miles on Eng. to have the 94 pump still running.The newer pump will last a long time.

[ 07-21-2004, 02:51 AM: Message edited by: Bnave95 ]

[rjschoolcraft]

Sounds like the classic FSD/PMD failure scenario.

[moondoggie]

Good Day!

Ditto ronniejoe.

In the old days, those in the know that drove F**ds wouldn't leave town without a starter solenoid in the glovebox; I wouldn't leave town with my 6.5 without a spare FSD.

Blessings!

Brian Johnson, #5044

[markrinker]

Agreed it sure sounds like an FSD problem, but its interesting that it waited until the truck was at 10,000 feet above sea level to fail.

Hmmmmm...

What if he's experiencing turbo boost maladys caused by an bad solenoid, vacuum line, or wastegate actuator? That would certainly cause black smoke (unburned fuel) combined with the altitude (less O2 to burn).

Its not clear where your post is written from - are you experiencing the same problems now down off the mountain?