Attention: TDR Forum Junkies For a few weeks now, I've been convinced my lift pump was failing (again). Mostly ran fine, but when I put the Comp box on a 5x5 WOT run, I could hear it cutting out at the top end and performance seemed ever-so-slightly sub par. However, the max boost was the same old 34 psi it's always been.
Then one day on my way to work last week, my truck up and died at an intersection. My truck and I suffered mild psychological damage while a Ferd towed us out of the way. While waiting for AAA, I called the dealer and told him to get ready for a dead lift pumpted truck. He asked how I knew. I said because it's been dying for two weeks, and now it quit, and the fuel filter is empty. I figured letting my fuel level get down to just under 1/8 of a tank was just enough of a test to cause it to go south.
Al, the manager of the service dept said, "You probably ran it out of fuel, and the injector pump needs to be reprimed. " He claims the sending unit for the gas gauges can get "off" and its risky running them that low, even though I've done it a hundred times.
I disagreed with him, but I didn't have time to argue. I had a Comp box to get stripped out before the tow truck got there.
So next day the truck is ready. Al says the lift pump was fine - within specs, and all they had to do was reprime the injector pump and she runs. And, oh by the way, there were some fault codes they cleared in the computer, which may have explained the cutting out behavior I was seeing before and blaming the lift pump for. What???? I just ignored them, figuring I'm still in for a new pump.
Well, low and behold, I checked the next time I filled up the tank and sure enough, something's changed. When my gauge reads 1/8 of a tank, I can put 30 gallons in. That's about 4 or 5 gallons more than it used to take at that level.
But the amazing part was what happened when I reconnected the Comp box. On my first try, I didn't get a good contact on the pump wire. Max boost was 30 psi and performance was pretty dull. When I got that wire on there right, the truck ran better than it ever has before and now my poor little Hy-35 is knocking out 38 psi, and there's no cutting out at the high end - HOLY COW!
Could the dealer have really made my truck run better by clearing a few codes??? I don't know, but I sure like the way it runs! I guess I'll put a fuel pressure gauge in and do my own diagnosis on the lift pump.
Then one day on my way to work last week, my truck up and died at an intersection. My truck and I suffered mild psychological damage while a Ferd towed us out of the way. While waiting for AAA, I called the dealer and told him to get ready for a dead lift pumpted truck. He asked how I knew. I said because it's been dying for two weeks, and now it quit, and the fuel filter is empty. I figured letting my fuel level get down to just under 1/8 of a tank was just enough of a test to cause it to go south.
Al, the manager of the service dept said, "You probably ran it out of fuel, and the injector pump needs to be reprimed. " He claims the sending unit for the gas gauges can get "off" and its risky running them that low, even though I've done it a hundred times.
I disagreed with him, but I didn't have time to argue. I had a Comp box to get stripped out before the tow truck got there.
So next day the truck is ready. Al says the lift pump was fine - within specs, and all they had to do was reprime the injector pump and she runs. And, oh by the way, there were some fault codes they cleared in the computer, which may have explained the cutting out behavior I was seeing before and blaming the lift pump for. What???? I just ignored them, figuring I'm still in for a new pump.
Well, low and behold, I checked the next time I filled up the tank and sure enough, something's changed. When my gauge reads 1/8 of a tank, I can put 30 gallons in. That's about 4 or 5 gallons more than it used to take at that level.
But the amazing part was what happened when I reconnected the Comp box. On my first try, I didn't get a good contact on the pump wire. Max boost was 30 psi and performance was pretty dull. When I got that wire on there right, the truck ran better than it ever has before and now my poor little Hy-35 is knocking out 38 psi, and there's no cutting out at the high end - HOLY COW!
Could the dealer have really made my truck run better by clearing a few codes??? I don't know, but I sure like the way it runs! I guess I'll put a fuel pressure gauge in and do my own diagnosis on the lift pump.
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