New tires, shocks(6), Clutch master and slave, wiper motor, battery and terminals, properly gaped plugs, wires, distributor cap, button, pcv valve, fuel filter, egr valve, egr sensor, idle air control valve, throttle position sensor, timing set at 10° BTDC by a certified FORD mechanic(local dealership), engine coolant temperature sensor, high pressure fuel pump(E2000) after fuel pressure test at 30 then immediately falling to 0...... and she's still surging at idle.

Every injector is "ticking" away when I placed a screwdriver against each one and "listened". I can smell she's running rich belching smoke at startup and though not as much volume but still puffing white smoke during surging at idle and eventually dying.

So, what's next?

 

Blown head gasket? Have you checked the oil?

 

Your fuel pressure is too low. a 4.9L engine should have 45-60 PSI Key On Engine Off after a few cycles of the key. At idle it should be 45-50 PSI. Since you only got 30 you could have a weak pump, faulty fuel pressure regulator or a bad injector stuck open. Given the pressure drops off so quickly I would start by inspecting the regulator.

White smoke? Usually means water, meaning a head gasket problem.

Surging idle could be a vacuum leak(s), faulty IAC or worn throttlebody.

 

Thanks! My post wasn't very clear in that I did install a E2000 high pressure fuel pump due to the low pressure. I"m now getting 55PSI but then falls to 50(KOEO)... sustained pressure at idle. My next move.... maybe a fuel pressure regulator???

 

Update... I've also changed the radiator and hoses, water pump, thermostat, fan clutch, and smog pump(got rid of that grinding sound). I placed a screwdriver handle to my ear and alternated between "alternator" - "smog pump"... there was a marked difference in the sound and this is how I determined it was the smog pump. Took her for a test drive( still haven't fixed the rough idle ) and she started to sputter. Now what? I plan on changing the fuel pressure regulator and probably the injectors to see if that cures what's ailing her. Oh... and I only run 100% American refined gasoline at 93 octane. I'll keep updates coming as I continue the journey of the 1988 Ford F-150 4.9l 300. Thank you for your help.

 

I have not checked the head gasket. I have checked the oil and it seemed okay.

 

Thanks. I mentioned earlier I had changed the high-pressure fuel pump(on the rail) and that seemed to remedy my fuel pressure problem. She's now at 55PSI at KOEO and holding at 50PSI at KOEO. I haven't checked the head gasket. Thanks!

 

Puffing white isn't good. I'd be looking at a headgasket issue as well .