# 2018 Sedan fuel pump humming/pulsating.



## 6speedTi (May 18, 2018)

Ok, I've noticed a pulsating humming noise from my fuel pump in the fuel tank. I can hear it making a pulsing or surging noise sitting in the vehicle with no radio on. It's definitely the intank fuel pump. I have 24,000 miles and use top grade diesel fuel with diesel kleen additive (gray bottle) for additional lubrication. Fuel level can be full or half. It makes no difference. When I just use the push start button to activate the pump and engine off the fuel pump makes a steady louder noise. It doesn't sound normal. I'm curious if anyone else noticed this? The pulsating sounds like it could be a impeller vibration due to out of balance or a bad bearing in the pump. The pulsating could also be the pump bleeding fuel back to the tank based on demand. But with the engine off and pump running it is steady and noticeably louder. I would appreciate if someone can give this a try with their vehicle and reply with your findings. I just want to confirm if this is normal or if I have a failing pump. Thanks.


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## MRO1791 (Sep 2, 2016)

Next time I drive mine I'll take a listen. From last fuel filter change I can say some pump noise is normal. BTW, do you keep your take above 1/4?  These pumps are cooled by the fuel, and running down to E on a regular basis will shorten the life of the pump.


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## 6speedTi (May 18, 2018)

MRO1791 said:


> Next time I drive mine I'll take a listen. From last fuel filter change I can say some pump noise is normal. BTW, do you keep your take above 1/4? These pumps are cooled by the fuel, and running down to E on a regular basis will shorten the life of the pump.


Yes I always keep it above 1/4. 
I know pumps make a suttle steady humming noise if it's quiet enough. This one caught my attention. The pulsating humming is what I'm concerned about.


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## 6speedTi (May 18, 2018)

Update:

The fuel pump sounds normal after it sits for a while such as overnight or after work. I took a short drive and I can hardly hear the pump but it is a low steady hum which is how electric fuel pumps are normally. I also turned on the ignition without running and I can hear it but very low and steady. So it appears that it after it runs for a while it begins to get louder and pulsating. I'll hook up my scanner and see what the fuel pressure reads at the pump.


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## Cruz15 (Mar 17, 2016)

I have 31000 miles and the pump sounds essentially the same as new, without engine running. I have used scanners on it since I bought it.


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