Q: Need to cycle fuel pump on and off two or three times before starting. Fuel pump or pressure regulator?

asked by on September 15, 2017

Suddenly hard to start. When not driven for 24 hours starter keeps chugging until I switch off ignition and try again, then it starts. Or, if I turn key on five secs, turn off and repeat, so I cycle fuel pump, before starting, it starts right away. Is this fuel pump or fuel pressure regulator? (Battery is fine, 12.6 volt unloaded 12.2 loaded. I guess at 30k miles spark plugs are fine.)

My car has 30000 miles.
My car has an automatic transmission.

Hi Peter. Thanks for contacting us tonight. What you are describing is common with a faulty fuel pump relay or pressure regulator - as opposed to the fuel pump itself. If you’re able to ’cycle the pump’ that typically indicates that the relay is not supplying power to the pump consistently - or the pressure regulator is starting to show signs of wearing out. It is also possible that the fuel filter is clogged with debris. I would start by checking the fuel pump relay to ensure it’s not loose, corroded with debris or damaged, followed by the fuel regulator and finally, double check the fuel pump ground wire connection - as this can also be a source of this problem.

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