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Rising rate fuel reg

#Brock

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Should a rising rate fuel reg show presure with ignition on?
Or only once the motor is cranked?
As mine shows zero on reds but hits 40 when I crank it over.
 

delcowizzid

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if the pump primes it should show pressure.but most cheap aftermarket jobbies will instantly lose pressure so may not see pressure after priming
 

car_driver

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The fuel pump runs for about 10 seconds when you switch the key to ignition. It should hold about 40 - 50psi with the stock regulator without leaking down when the pump is not running. If you lose pressure when the pump is off the engine will be hard to start first go.
 

#Brock

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Thanks for the feedback I have no fuel pressure with Reds on or whilst cranking the motor however when I Bridge the fuel pump relay my rising rate Reg go straight to 45 PS I have had a MAFless tune with kalmaker and may have been locked out due to removing the battery have been told to turn ignition on for 1 minute off 1 minute then motor should start. Can hear both Pumps priming with ignition on but no fuel pressure show's on the rising rate Reg only once I Bridge it have checked all fuses and swap relats around so they're all fine.
 

#Brock

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I've got spark but the plugs are bone dry so there's definitely no fuel getting there can't figure out why fuel is getting to the reg when I Bridge it but not when I turn the ignition on relay seems fine have swapped it out with other relays that work.
Car has been running fine until my lift pump **** itself so swapped it out with a new one can hear it priming the surge tank and can hear my external Bosch 044 working but still no fuel pressure on the rising rate Reg only when I Bridge it. Even if the ecu was locked I would still be getting fuel to the rails injectors just wouldn't pulse this is correct
 

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Do you have the 044 running on the same relay / circuit as the tank pump? If so it's drawing too many amps and probably frying the fuel pump relay?
I would put a second high amp relay in that is triggered by the same wire as the original relay and run a new wire to the 044.
 

07GTS

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all the referenced regs do is with pump on show pressure say 58psi and then once started will show less from the vacuum and then under boost it will increase above 58 by the amount of boost u have, the end result is the pressure at the injector tip (when spraying) stays at a constant with the vac or boost within the manifold
 

#Brock

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Have separate relay,fuse n thick wire to Bosch external. Pumps prime but doesn't show on the reg when I hit the reds.
Running a surge tank without one way valve it won't hold fuel pressure yes?
But should show on the reg when priming ignition on for few seconds yes? Have nothing on the reg when I turn ignition on
 

#Brock

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Ok so had another go at it this morning checked all fuses visually and with ohms resistance so all good,checked for any short circuits with multimeter on amps while pulling each fuse and testing circuit the only two that were drawing power were the radio fuse 0.02 amps for memory and engine control bcm fuse 0.03.
Rising rat reg goes straight to 50psi on prime but nothing when starting the car. Checked this visually also by taking the fuel return line off before rising rate reg. Pumps fuel when I bridge fuel relay which makes me think the ecu is not sending signal to pumps when starting as it must be locked from unplugging the battery as tuner said it would. Tuner coming out next week with his ecu with my tune on it I'll let you no how it goes. When taking battery leads of the ecu will go to security lock and the injectors won't pulse but there will be spark which there is. If so no injector pulse from ecu could mean no signal to pumps when Starting/cranking which may just explain fuel on prime but no fuel whiilse cranking to start. Has anyone had a Kalmaker tune or any experience with security lock out if battery is disconnected? Tuner said to unlock it I put ignition on for one minute then ignition off for one minute then it should unlock and the car should fire, have tried many times without success see what happens when he comes over with his ecu with my tune on it!! Just want to get this blown 5ltr going again. Any more input would be appreciated..
 
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