86 F150 302 v8 EFI...Fuel Injector problem

[79spitfire]

Hey everyone, thanks for taking the time to check my post out.
The problem im having seems to be that the fuel injectors arent shooting fuel into the combustion chamber. I have spark, I have fuel pressure, and fuel in the fuel rail. A self test (KOEO) I did showed all relays and such were fine for the "hard" test codes, but the continuous memory codes shot me an 18, which according to the book is a " loss of TACH signal to the Electronic Control Assembly". If im not mistaken the TACH would be the number 2 wire on the Ignition Control Module, which i tested and has current all the way to the ECA. And I know that the ICM is good cause I just replaced it the other day. Please help me, I dont have much more hair to pull out. Thanks

[FORDTRACMAN]

You need to check fuel pressure with a gauge.You need around 35 pounds of pressure.You might also pull a spark plug and see if it's wet or dry.

[79spitfire]

ya, the fuel pressure is right on, and the plugs are dry as a bone. possibly fuel pressure regulator? will find out today. any other suggestions? i would appreciate it, thanks.

[FORDTRACMAN]

Disconnect vacumn from FPR turn key to on for 5 seconds-do it twice and see if you have gas coming out of the FPR if yes,replace.

[79spitfire]

well, i replaced the FPR yesterday and i still get nothing. i guess my next step will be to replace the Stator. Could there be anything im missing? I've replaced everything having to do with ignition, and done all checks on wires and relays, fuses, fuseable links, etc....

[FORDTRACMAN]

Was your FPR bad? If you still have low fuel pressure it almost has to be fuel pump or an extremely plugged fuel filter.

[79spitfire]

would the only reason my injectors arent opening be because of low fuel pressure? The last time i tested it it was putting up about 35-36 pounds of pressure and that was a few days ago.

[79spitfire]

ok- i checked my fuel pressure again and now its not holding any pressure at all. I hooked the guage up, turned the key to the on position, and grounded the pump using the diagnostic connector so i could watch it. I let the pump run for about twenty to thirty seconds to see exactly how much pressure would build up, unfortunatly it maxed out at thirty pounds. As soon as i let off the pump the pressure dropped immediatly back to zero. So i have a problem there now for sure. Would the low fuel pressure cause my injectors not to work at all? The injectors have current so i know thats not the problem. Also, if the low pressure in-tank pump wasn't working would the high pressure pump still be able to suck fuel from the tank? Cause i have a steady flow of fuel but not the specified pressure. PLEASE HELP.....THANKS ALOT

[79spitfire]

Is the ballast resistor between the coil and the computer necessary, or can i bypass it? Please someone read my whole thread and help me out, i need this truck to run. Thank you in advance.

[FORDTRACMAN]

You may have to get hold of a manual to cover the vehicle you have,some early EFI used low pressure pumps.Your low pressure pump will push fuel to high pressure pump if equipped.Low pressure pumps--[volume]6 oz min in 5 seconds

[mustangmike351c]

if you have no tach signal then the ecu doesnt know when to firer the injectors and will not until it get a signal.

[ManOnTop]

I have the same exact problem. However, I went ahead and replaced the ECM and I still have the same problem. The injectors are NOT spraying any fuel and only the ECM controls the injectors. I do know that someone else installed a new ICM, because the truck had no fire when I initally checked it out. Another thing that I noticed is that my truck WILL NOT enter diagnostic Self-test mode. These trucks are NOT electronically sound.