Fuel problem

[CarsonChris]

My project BII is getting close to being operational. I started it yesterday and drove a few blocks. Parked it and my son started it and tried to drive it. It stalled on take off. Wouldn't re-start for an hour. Started up again and ran strong. Turned it off and now it won't fire. It seems to be a fuel issue.

While driving yesterday it would sputter shifting between 1 and 2. Ran stronger with more rpm. Less lag in third.

 

[RonD]

Fuel issue would either be a no start(0 fuel pressure) or lacking power at higher RPMs(low fuel pressure), power wouldn't get better with higher RPMs.

Assuming 2.9l with automatic, TFI spark with MAP system(speed density)?

If you add fuel manually to the intake and try to start it does it fire up then die, that would be fuel issue.
If engine doesn't fire with fuel added then TFI would be the most likely issue

You could check the Fuel Pump Relay on passenger fender, Green Base, when key is turned on this relay should Click and 2 second later click again, you should hear the fuel pumps(assuming you have two) come on for those 2 seconds.
The EEC relay(Brown base) is next to the FP relay, EEC relay will also click with key on but won't have the second click, it stays on.

 

[CarsonChris]

Intermittent fuel pressure. Had it for a bit, squirt from fuel rail to barely a dribble.

 

[RonD]

On the dual pump systems there is a splice near the high pressure pump(in the frame rail under drivers seat), it is a factory splice but can corrode.

The 7psi pump in the tank was used for carbed engines, when Ford went to fuel injection they added the high pressure pump(40psi) in the frame rail and just tapped into the power going to the in tank pump, the splice.
(I think '88 got high pressure pump in the tank)

These system also have a reserve "bowl" between in tank pump and HP pump, it looks like a canister fuel filter, these can clog up.

Also on older vehicles the "sock" on the in tank pump can get clogged up.

Either of these can allow fuel to seep in while sitting and when you start the engine it runs OK, but when fuel is used up engine dies and won't restart until more fuel can seep thru the clog.
But wouldn't explain higher RPM getting better.

 

[CarsonChris]

Checked the relay and hear the 2 clicks. Climbed under and hear the fuel pumps engage.

Changed the TFI and adjusted timing when I switched transmissions.

I don't have an leaks from the FPR. checked the vacuum line and it's dry.

 

[RonD]

Turn the key on, count to 3 then turn key off
repeat 2 more times
You should get about 10psi of pressure each time pumps run for 2 seconds

So after 3 times it should be up to 30psi, then try to start

Could be check valve in high pressure pump isn't working, or FPR is stuck open or leaking enough so pressure can't stay high, and fuel is running back to the tank.

 

[CarsonChris]

My fuel gauge isn't working either.

 

[CarsonChris]

Where do people cut the quick access for the fuel pump change in the tank?

 

[CarsonChris]

Got the BII started again. Running pressure is 32 psi at the schraeder valve. Aprox 10 psi when turning the ignition switch. Goes higher as engine cranks.

I cleaned the IAC. Could it be something so simple or could it be the BII sat for 4 years and just be bad gas?

 

[RonD]

Water is heavier than gas and you get some water every time you get gas, and unless you get bad gas(lots of water), it isn't an issue since driving around keeps water mixed and only a little comes to the engine with the gas.
Sitting for 4 years would mean any water would be at the bottom of the tank, where fuel pump pick up is, so you will get alot of water when first starting.
Octane is also lower in the gas itself from sitting, so harder to get burning.

Run some fresh gas, 5%-10% ethanol mix helps absorb any remaining water.

Can of Seafoam, or similar, injector cleaner in the gas tank will also help clean up the varnish in the fuel system and injectors

 

[CarsonChris]

She's firing right up now after changing the coil and cleaning the connection. My fuel gauge isn't working though and it still seems a little bogged down.

 

[RonD]

This is a 2.9l wiring diagram: http://www.therangerstation.com/tec...es/Diagrams_ElectronciEngControls2_9_1of3.JPG

It has the wiring for the fuel tank shown, lower left.

Pink wire is the power for the fuel pump
Yellow/white stripe wire goes to the Fuel gauge

The sender in the fuel tank is a Variable Ground, in 1987 73ohms is Empty, 10ohms is Full.
So if you ground the yellow wire fuel gauge should go to Full, you can just pierce that wire with a pin and then Ground the pin with another wire and see if fuel gauge goes to full.
If it does then the sender in the tank is bad, very hard to find these so rebuild if possible is best bet, and it could just be the float, it is full of gas so stuck at the bottom of the tank.

If gauge doesn't go to full then gauge is the problem.
Google: ford anti-slosh module

Not sure if they had this in '87 but I think they did
Gauge also uses a Pulsed 5volt power supply, on the back of the dish I think.

 

[CarsonChris]

Thanks for the help!