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I'm having an issue with my project 1984 Ford Ranger 2.8 L. I've upload a video of the issue here.

After starting up, the engine stalls after a few seconds. I've adjusted the timing to get max manifold vacuum (need to borrow a timing light) and it's holding steady around 19 inHg.

The engine bay is currently a mess, but it's using CFI from a Cougar 3.8L, a fairly common swap. It's also running straight off the manifold w/o an exhaust yet.

Does anybody know what could cause this, or is there anything that I should be checking? Any leads would be helpful.

Edit: I've tested the fuel pump after installing it (with the ignition ON and engine OFF) and it was providing 40psi. I will test it again w/ the engine running once the auto store opens tomorrow and rent a fuel pressure tester...

  • Do you mean Throttle Body Fuel Injection? What are you using to control the fuel injector? It sounds like your control system is working for pump / cold start assist, but not providing fuel at all for normal run operation. What fuel pump are you using? how are you driving the pump? How are you controlling fuel pressure at the engine? Frankly I'm surprised it wasn't just a whole lot easier to just rebuild the 2.8L carburetor that came with the vehicle. – zipzit Dec 25 '16 at 20:59
  • Does anything at mechanics.stackexchange.com/a/32989/9884 help? – Jason C Dec 25 '16 at 21:00
  • @zipzit - yep, throttle body injection. The 3.8L ECU is controlling the 2 injectors. The ECU is also controlling a relay that provides 12V to two pumps (from a 2.9 Ranger). There's a ~40psi regulator on the throttle body. – Kevin Evans Dec 25 '16 at 21:02
  • Er... so what happens to the excess fuel pressure? Sometimes the manufacturer provides a second tube to the fuel tank and excess fuel is bled off and pushed back to the tank. (really bad for emissions). Other times there is a single fuel line from the tank to the engine and the fuel pressure is controlled with a Pulse Width Modulated (PWM) signal controlling the fuel pump. How does yours work? The PWM fuel pump driver module is not an easy beast to add in after the fact. That is critical to maintaining the correct pressure during all conditions. – zipzit Dec 25 '16 at 21:19
  • There's a 1/4" return line that goes back to the tank. Essentially the ECU has a +12V out that powers a relay. That relay then goes to an inertia switch (not present currently) then to the pumps. – Kevin Evans Dec 25 '16 at 22:09

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