In the January/February 2011 issue of Truck Trend
, I was reading the "Spontaneous Shutdown
" letter in "Truck Trend Garage
" and thought I'd write to let you know about an incident where I had the same problem. I used to own a 1994 Suburban that ran great, and used it to pull a pontoon boat from Lancaster, California, to Lake Havasu via Highway 40. Some of the hills on the 40 are fairly steep. On the way home on one of these trips, I came to the bottom of a hill getting ready to climb the next grade. The vehicles ahead of me weren't going very fast, so I built up speed and started to pass them in the right-hand lane when all of a sudden the engine died. After getting over to the side of the road and checking under the hood, I found nothing out of the ordinary, so I got back in and tried to start the vehicle. It started right up and didn't have another problem the rest of the way home. My next trip to the river, it happened again-this time, on the way there-and I was able to put the vehicle in neutral, turn off the ignition, and when I restarted it, everything was fine. I didn't have another problem on the trip. I suspected that the issue was fuel-related. Since I bought the vehicle used, I don't know if anyone changed the fuel filter, so I did. I never had the problem again. I hope this is helpful to others who may have had this problem. It's really a weird feeling to drive along and the engine stops with no warning.
Answer: Thanks for the input! Although the fuel filter may be a viable cause of the problem you experienced with your ex-Suburban, the symptom description sounds a bit irregular. Usually a clogged fuel filter produces a somewhat smooth loss of power as the engine is deprived of the necessary volume of fuel. Your condition sounds more like an abrupt shutdown of the engine. But you never know, going hard on the throttle up a steep incline may have caused a more dramatic loss of power, and the fact that it started back up with little fuel demand (idle speed) also fits the bill of a clogged filter. The engine not starting right back up on the side of the road would indicate more of a hard fuel system (or ignition) failure, such as the fuel pump motor failing or the loss of a power or ground circuit that runs the pump. Here's something interesting I've noted on the majority of late-model vehicles: There's no inline fuel filter. Instead they use a simple screen before the fuel pump within the fuel tank. I don't have an engineer's confirmation on this one, but the automakers may have realized that standard fuel filters have been doing more harm than good, meaning those tiny particles plugging up the finely meshed filters could've passed right through the pump, lines, and injectors-and burned up in the combustion chamber-without causing a problem.
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