trying to determine fuel pump problems

[paintdrying]

I need to make sure my fuel pump is bad before replacing it. I am going to test it here in a few moments in regards to pressure and volume.
What is happening is the ecm-1 fuse blows after about ten minutes of running the van. After the van cools down I replace the fuse and it is good for another ten minutes. Everything is fine up to the point the fuse blows. I know the pump could do this, but how can I tell for sure what is happening.
Has anyone ever heard of a pump heating up then blowing a fuse?

[Jasen]

We've seen the wiring harness's inside and out of the tank pretty cooked. If your getting to much resistance do to bad wiring your straining the system and it could get to the point, say 10 mins, and pop the fuse.

[paintdrying]

anyone know what spot on the multi meter to check amperage?

[RECox286]

You will need a 'clamp-on' style meter to check for amps in the circuit. However, consider this: If the fuse blows, it is drawing too many amps

and if you don't get it under control, then the wiring will be next in line.

Sounds like the pump...

Uncle Bob

[paintdrying]

Just checked the pressure. Holds at 55 psi, goes almost to 60 psi. Will see here in a minute if it is going to fall. Not going to drive with it right now

[paintdrying]

What are the pressure measurements for a fuel pump. I drove it around the block and it will go to 60 psi. 55 seems a little on the low side.

[Leeann_93]

GM doesn't publish running fuel pressure - there are too many variables.

KOEO, it must have 62 psi and hold within 5 psi for at least 10 minutes.

[paintdrying]

This confirms what I thought. The fuel pump is dieing. I just tried to order one from rock auto. Something about them being unable to complete my order. Now I will have to call them tomorrow. Can't help but wonder if rock does not let you order after hours.

[Corsemoto]

Which one are you ordering? I just put a new Delphi pump in my van from Rock Auto. Fuel filter is a good idea too.

[paintdrying]

I got the delpi with fuel sending unit lock ring. The sock filter on the pump is not replaceable on the new pumps. If I did this job again I would replace those darn quick disconnect impossible to unconnect fuel lines.
I put a new ac delco filter on. The old filter had fresh metal shavings in it.

[chevymaher]

I got the delpi with fuel sending unit lock ring. The sock filter on the pump is not replaceable on the new pumps. If I did this job again I would replace those darn quick disconnect impossible to unconnect fuel lines.
I put a new ac delco filter on. The old filter had fresh metal shavings in it.

Come on that is the new improved technology your talking about. It works better because, we were told it does. Personal experience you had, has nothing to do with reality. Think it was easier. Oh god just say it is so. So we don't have 19 page long replies saying it is easier. With design papers proving the point. Written by people who never worked on a car in their life.

[paintdrying]

Was telling my dad about replacing the fuel pump. It made absolutely no sense to him why they would put it in the tank, and why was it over $300.
He was telling me he had his fuel pump go out and it was two bolts and cost around 7 dollars. I had to explain to him how cars have improved so much. Now everything is better Dad. Everything is controlled by a very complicated system. Hard to fix. Expensive for the parts. But you save a few miles per gallon.
He just kept going on, why the heck is the pump in the tank? Well Dad it keeps them cool.
Well, that sounds like a good idea, but he said he never had a problem with his old fuel pump getting hot. Then I tried to explain that it is electric and submerged under fuel. Wires and fuel lines all under the fuel.
Try as he might my Dad could not for the life of him could not understand how this expensive pump buried deep in the tank was better than the one he had.

he will never understand I guess, he does not realize how lucky we are. Poor guy

[RECox286]

Yer dad's pump was located on the engine, and driven by a cam lobe. It's job was to pull fuel out of a remote tank, then pressurize it to

roughly 5-7 psi. All doable with that style of pump. However, it left a huge gap in that when the fuel lines got hot, they were susceptible

to vapor lock, which means the engine stopped working due to fuel starvation. When EFI was born, the mechanical pump idea went the

way of the dinosaurs. Fuel requirements dictated that higher pressures were needed, also when the fuel pump, now a remote electric motor,

was placed in the tank, it didn't have to pull the fuel, just push, which is more efficient for a pump to do. It also means that there is

positive pressure from the pump to the injectors, and the heat problem (vapor lock) is no longer in the equation. Bottom line, the

system is more reliable, but when it does break down, becomes more of a PITA to replace, and obviously, more expensive.

The joys of the better mousetrap...

Uncle Bob