QuestionQUESTION: I know that the pump hums when you turn the key to prime the system, but last 2 nights it seems like the hum from the pump has been louder. My friend who works on motors n stuff says that if you can hear the pump its working, but if it gets louder is it a sign its going to stop working?
also does any additive for fuel like that mystery oil stuff lubricate the pump or is all of that additive stuff commercial hype to get people to spend money?
ANSWER: Frequently a fuel pump that is much louder is approaching failure. Is that a guarantee of failure? No, but it's a distinct probability.
Fuel additives are for the injectors, intake tract, and combustion chamber, and I have never heard of any that address fuel pump issues.
scotty
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QUESTION: ok. the night i noted the problem the car ran fine. came home parked it and went to leave the next night it would not start, the pump didnt make noise. we dropped the tank to get a new pump and before going to the junkyard we hooked up a battery to the pump and it worked fine, it sprayed fuel like crazy. but in the process found the sending unit wire was fried, so we replaced that. took the tank back to the car hooked up the electric and the fuel line and turned the key and it worked . fixed broken bolts and rusty things etc. raised it back up and tightend every thing , turned the key no pump. banged on the tank and it worked, got it running but he idle would go high then really low. adjusted the idle to where it stayed at 1100 even with heat and lights being turned on. i dont know if we had a short or if the pump is failing, I have no idea where to go from here. I dont trust it now, and I need this car for my paper delivery job.
ANSWER: It may be that the fried wire has to do with the pump issue. (bad ground could have grounded through the sender wire) Only for sure way to trust it is replace it, and make sure the power and ground wires are better than perfect. That's what I do with my vehicles that I have to trust to get me to work at 4 AM in the winter in the Colorado mountains.
scotty
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QUESTION: we replaced the pump with a new one, but he sending unit for gauge is broken, so the gauge doesnt work. will this affect the operation of fuel system? i plan on going to get a new gauge unit next week. After installing new pump idle is still jumpy, but i wonder if that was due to air in the line after doing all this work..? I'm sure i'll be back in touch.
AnswerThe only issue with a bad sender is that you don't know the fuel level. Keep it more full than you usually would, or carry a gas can. I have had a marginal sender for five years, and just carry a gas can. The idle issue is probably due to adjustment issues. I can't remember the adjustment procedure, but do remember that it is sufficiently long and complicated as to require access to the factory book. (yeah, I know, I tell EVERYONE to get a factory manual, but it really IS worth it when dealing with electrical/electronic/injection issues)
scotty
