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Known good install, will not start

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This is a rock crawler that I purchased and was told it starts and runs, a year ago.  I believe it is a Go 400, with inline fuel pump, on a ford 351w

What I know.

It turns over and has spark.  If starting fluid is sprayed, it will fire on that.

There is a fuel pressure gauge on the inlet, right at the throttle body, and it pumps to almost 60psi when the key is turned and then the pump shuts off and it bleeds back down.  When it's cranked, the pressure goes back up to 60 until the key is released and then it bleeds back down.  I thought it was supposed to maintain pressure even after the pump turns off, like factory tune port injection?  I replaced the fuel pump with a fitech and it acts exactly the same, original was a Bosh.

The hand held controller is functional and remembers parameters and settings.

The red and the white wire have power when the key is on and when it is cranking.

When cranking, handheld reads RPM, but does not read vacuum?

There are no vacuum ports used from the manifold.  The PCV and Brake booster ports are blocked.  I believe when I got it, one was open, no hose or anything.  There is a hose from fitech to I believe pressure regulator on the fitech.

All help is most appreciated

Thanks

 

I guess the first thing I would check is your voltage reading at the wire going to the fuel pump with switch on and while cranking.   If with the switch in the on position, your fuel pump wire voltage drops way below 12 when your pressure is not reading near 60, there must a problem with fitech not reading fuel pressure correctly, because it's suppose to maintain pressure with the switch to on.  If this is the case, I would connect the fuel pump directly to voltage with the key on and put in a external regulator.  Could be your fitech internal regulator has failed.

This isn't answering your questions but it may just help if you haven't the original installation documents.

I have attached scans of the installation instructions I received in the box when I bought my GoStreet 400 in 2016

They cover:

GoStreet 3003 throttle body (part No 3003) - this is the basic throttle body without timing control

GoStreet hand controller  (this is the original controller without arrows around the joystick)

Fuel Command Centre 4003  (which sound like you don't have - but I have included it anyway)

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Are you getting a prime shot of fuel with initial key on?

Quote from bdhulderman on January 20, 2021, 1:58 pm

I guess the first thing I would check is your voltage reading at the wire going to the fuel pump with switch on and while cranking.   If with the switch in the on position, your fuel pump wire voltage drops way below 12 when your pressure is not reading near 60, there must a problem with fitech not reading fuel pressure correctly, because it's suppose to maintain pressure with the switch to on.  If this is the case, I would connect the fuel pump directly to voltage with the key on and put in a external regulator.  Could be your fitech internal regulator has failed.

So it works like a regular factory port injection, where turn the key, fuel pump turns on, gets pressure, pump turns off (not sure about that) but pressure holds?  So the pressure regulator is saying, I have pressure, turn off?  With a running engine, (hopefully I have one some day)  does the fuel pump turn on and off or even some duty cycle to maintain pressure?

The other thing noticed is when the fuel pump is running, it is returning all of it back to the fuel tank at high pressure.

Thanks for your input!

 

Quote from robanzac on January 20, 2021, 2:13 pm

This isn't answering your questions but it may just help if you haven't the original installation documents.

I have attached scans of the installation instructions I received in the box when I bought my GoStreet 400 in 2016

They cover:

GoStreet 3003 throttle body (part No 3003) - this is the basic throttle body without timing control

GoStreet hand controller  (this is the original controller without arrows around the joystick)

Fuel Command Centre 4003  (which sound like you don't have - but I have included it anyway)

Thanks for these documents!

Quote from ajax-1947 on January 20, 2021, 10:57 pm

Are you getting a prime shot of fuel with initial key on?

Can I just look down the barrels and see this with key on or key cranking?

Quote from rockyroadster on January 21, 2021, 6:40 am
Quote from bdhulderman on January 20, 2021, 1:58 pm

I guess the first thing I would check is your voltage reading at the wire going to the fuel pump with switch on and while cranking.   If with the switch in the on position, your fuel pump wire voltage drops way below 12 when your pressure is not reading near 60, there must a problem with fitech not reading fuel pressure correctly, because it's suppose to maintain pressure with the switch to on.  If this is the case, I would connect the fuel pump directly to voltage with the key on and put in a external regulator.  Could be your fitech internal regulator has failed.

So it works like a regular factory port injection, where turn the key, fuel pump turns on, gets pressure, pump turns off (not sure about that) but pressure holds?  So the pressure regulator is saying, I have pressure, turn off?  With a running engine, (hopefully I have one some day)  does the fuel pump turn on and off or even some duty cycle to maintain pressure?

The other thing noticed is when the fuel pump is running, it is returning all of it back to the fuel tank at high pressure.

Thanks for your input!

Yes, turn key to on, pump runs until pressure is reached, pump turns off.  If pressure starts to dip below target, pump starts up again to maintain pressure.  Regulator just allows enough fuel to return to the tank to keep the fuel pressure from exceeding target pressure.  It opens when the pressure exceeds target.  I also put in a one way valve in the fuel line, so that when I turn the car off to go into a store or something and come back out, it will still read the target pressure and I can just immediately turn the key to crank.

 

 

Is the Pump pwm setting correct ?

main menu> pro tuning> initial setup >  fuel pump control

It needs to be set at 75 with a normal efi fuel delivery set up   i.e  tank - high pressure pump - throttle body- return to tank

If you are using a Fitech fuel command center for fuel supply then it needs to be set at 40.

Operating pressure should be constant 58psi

Also - are you using the correct port for fuel return to tank ?

There is only one,  the other three fuel ports are all inlets (you block off the two you don't use)

 

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Though it is probably obvious, I should  point out that the photo above is for a fuel command centre  installation in which the return port is plugged.

In a normal setup that would have the return hose to tank.

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