F53ultrasport
New member
- Joined
- Oct 2, 2017
- Posts
- 1
First of all. Im new. Great info. Im going to save lengthy backstory for now. 1997 F53. Replaced fuel pump and filter. Starts and runs. Has 30 psi fuel pressurs at idle, pressure drops to 20 and teens as you drive it and it sputters and backfires. Gets worse the longer it runs til it will no longer move. Does anyone know what the voltage is supposed to be at the pump connector?
I measured around 6 volts with what i thought was a good ground at the frame. My thinking is that the pump needs closer to 12 volts to put out max pressure. I assume there is some voltage drop on a 35 foot coach, but not 6 volts drop.. Also, i have checked and cleaned the grounds at the engine block and frame rail at the passenger side front of the coach. It did not raise the fuel pressure.
Does anyone know if the pump is grounded else where besides the front?
I know there is a ground in the connector, but i thought that ran to the front near the battery and engine block where i just cleaned with a dremel.
I am going to run a wire from battery direct to pump and see what happens with the pressure.
Is it possible that the voltage supplied to the pump is supposed to increase as the throttle is opened and maybe 6 volts giving 30 psi fuel at idle is normal.
Thanks in advance for your ideas.
I measured around 6 volts with what i thought was a good ground at the frame. My thinking is that the pump needs closer to 12 volts to put out max pressure. I assume there is some voltage drop on a 35 foot coach, but not 6 volts drop.. Also, i have checked and cleaned the grounds at the engine block and frame rail at the passenger side front of the coach. It did not raise the fuel pressure.
Does anyone know if the pump is grounded else where besides the front?
I know there is a ground in the connector, but i thought that ran to the front near the battery and engine block where i just cleaned with a dremel.
I am going to run a wire from battery direct to pump and see what happens with the pressure.
Is it possible that the voltage supplied to the pump is supposed to increase as the throttle is opened and maybe 6 volts giving 30 psi fuel at idle is normal.
Thanks in advance for your ideas.