[Merylo]

I just put in my 5th fuel pump(83 280ZX 2+2 167K miles) in 3 months. This one lasted 20 miles. All the pumps I put in run noisy and the whirring (or grinding as it were) sound fluctuates at idle. Sometimes after the car dies if it sits 1/2 hour or so it starts and will run for 1-3 mile then Blaaaaaaa. no go and finally the pump goes out. The pump runs very warm almost hot to the touch even at idle and makes a lot of noise. Today I pulled the tank sending unit cleaned the strainer blew out the lines replaced the tank to pump line replaced the pressure regulator (had a spare one on hand) the lines going to and from the reg. and all the clamps on the lines thinking there might be an air leak. I used clear fuel line to see if i could spot any bubbles and noticed some on the return to tank line from the Pres. Reg. One of the injectors has a small leak. I think that might be the source of the air in the return line but would that affect the supply side of the system? Could the EFI system be sending overvoltage to the pump? I'm running out of ideas.

 

[SixBanger]

lets wait until somebody else confirms this but i could only think of two things that could cause your pumps to go out like that. one is overvoltage (making it run faster than it needs to, and it overheats), and the other would be a clog of some sort in your fuel lines. I'd definitely look into the overvoltage possibility, its happened to me (although on a '73 electric fuel pump).

 

[fallon]

the sure test for a fuel systen is to tee a fuel pressure gauge into the supply line immediately after the fuel filter. Pressurre should read 37psi. The maximum pressure the pump can deliver before its internal pressure relief valve opens is 60psi. If the pressure is too high the car will flood...lopeing idle, stalling and smell awful especially on start up. If the pressure is too low the car will stumble on high demand due to starvation. Both conditions will cause the pump to whine, Things to look for are bad regulator, crude in the tank, a fuel line that has delaminated internally. Out put voltager should be 14,2 or less depending on temperature.

 

[helowrench]

the fuel filter on this type of fi system is very prone to clogging and will starve the engine take the time to change the filter just to eliminate it from your worries