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I installed a fuel pressure cauge and pressure is around 39-36psi.
My problem is that the pressure drops suddenly to 15-20psi when I drive the car. Of course car drives horrible.
I have changed the fuel filter, no help.
When the pressure is ok and I turn off the engine, pressure stays up for many hours.
What can I test next? I heard about dynamic fuel pressure test but I haven't found out how to do it.
all you need is a new pump. They come with a strainer.
if you want a good one, the racetronix is a very popular upgrade.
These pumps wear out because everyone insist on driving hard with less than 1/2 tank of gas. Can't do that. The pump is cooled by being submerged in gas and the first time the pump sucks air it damages the rubber impeller. They do not like to be run hot or dry...
Half of what is found in fuel filters WAS/IS part of the pump as it disintegrates and sends chunks to the injectors.
Edelbrock sells the same pump as Racetronics. Summit Racing, Jegs and even Advance sells it online.
Summit also sells the Granatelli GRN-GM722-2 for $125. It is probably a Weber as well. The cheapy $69 pumps are probably not Weber.
Thanks to everyone. Another question. I measure about 12.6 volts from the fuel pump wiring harness when the car is running. At the same time I can read 13.7 volts from the battery. Is this voltage drop normal and will the fuel pump run correctly with 12.6 volts?
These pumps wear out because everyone insist on driving hard with less than 1/2 tank of gas. Can't do that. The pump is cooled by being submerged in gas and the first time the pump sucks air it damages the rubber impeller.
They do not like to be run hot or dry...
I think that is an old wives tale. At that rate, I'd be changing my pump every week. My car runs down to the bottom then gets filled up.
If it needs that much cooling, it would be a fire hazard. As long as fuel flows thru it, it is cooled. Now if fuel stops, the engine cuts out and the pump stops so no heating