Suburban engine stalls at 75 mph

chevrolet
suburban

#1

2002, Chevy, Suburban 1500, 4wd, 5.3L engine, 210,000 miles. Mass airflow sensor and both O2 sensors replaced last year in an effort to fix this problem. Original problem surfaced when the vehicle was shut down or running uphill and had about 1/2 tank of gas in hot weather. If stopped, the vehicle would not start until it had cooled down. Sometimes getting it onto level ground would be enough to get it running again. ( This accomplished by turning on the key and allowing the vehicle to roll back out of the parking place. ) If running down the road, getting to level ground after the stall, pulling to the shoulder and cooling the engine/waiting a few minutes and restarting the vehicle would work. This was before the above mentioned repairs.

Last weekend in 60 degree weather I was driving back from northern Michigan and as I headed up hill at 75 mph with the tank at 1/2 the vehicle did a high speed stall on me. Symptoms were: RPM showed 2000, but pushing down on the gas actually dropped the RPM no matter how feather-footed I was. This was tried several times. I turned on the 4 ways and moved toward the shoulder and at 50 mph finally got the thing to restart. The rest of the trip home was uneventful.

I had a 2001 Suburban with the same specs which did this same thing until a factory recall that got me a new fuel pump. I asked about the recall the last time my truck was in for service and they said it does not fall within the serial numbers for that recall. Fuel filter replaced about 9 months ago. Co-incidentally but not necessarily related is that my battery with less than 3 years of a 7 year warranty was draining itself in less than 2 days this last winter.

So, any suggestions? I’m stumped.


#2

Your fuel pump pickup is not on the bottom of the tank, anymore or the pump filter sock is flopping around and blocking the pump. The fact that you describe what could be interpreted as fuel starvation while going up a hill. Repositioning on level ground to fix it tells me to look to the in-tank fuel pump and plumbing. I’m amazed your previous mechanic didn’t key into this.

Drop the fuel tank, pull the sender/fuel pump assembly and I think you’ll find the problem. With 210,000 miles, your fuel pump is not long for this world anyway.


#3

It certainly does sound like a failing fuel pump. I have no idea what the recall would have been about. But a fuel pump is a wear and tear item. This one has 12 years and 210K on it. Needing a new one would not be unusual at all.

Of course, you don’t have to guess about it. You just need a fuel pressure gauge and if basic, static checks don’t show a problem, the ability to check the pressure while in failure mode.


#4

Or a plugged fuel filter. Have you ever replaced the fuel filter?


#5

Good catch @melott, I forgot the fuel filter! Whatever the outcome, change the fuel filter. Changing the pump will likely loosen some crud for the filter to catch.


#6

The OP said the fuel filter was changed 9 months ago.


#7

Is the check engine light on? Have the active and pending codes been read? If so, what are they?


#8

I had the same thing happen on my 02 Tahoe on I 95 in Boston and it ended up being the Fuel pump, I’m amazed you got through 210K with the original, mine went on my after 90K, however, to prevent this in the future try keeping more than a quarter of the tank full


#9

A mechanic can drive the truck with a temporary fuel pressure gauge installed to see if the fuel pressure drops out when the power loss occurs. Possible bad fuel pump.