IDIs do not use oil to fire the injectors so probably not

 

Thank you fine Sir!!!

As was said below, the IDI does not use a HPO system to fire the injectors. I would look at a lazy Glow Plug system or a bad IP pump.

 

ok, so i had the chance to hook a scanner and look at the truck on datastream. the HPOP has almost 600psi when cranking and 700psi at idle, works like new! LPOP also tests out within specs according to AllData. sorry for the dissapointment guys haha

so after getting a couple opinions, and im really leaning towards this too, but the theory is now that its sucking air somewhere in the fuel system. apparently there are what ford calls "sleeves" with O-rings inside where they connect to the cylinder heads.

Any Opinions?

I also came up with an EBPV code, scanner says its reading 23psi of exhaust backpressure with the key on, engine off. which is obviously wrong haha, so i checked out the voltages and everything and i've determined the sensor is bad. so i will change that asap.

 

It will test okay once the truck is running. Do the OBS trucks have an oil pressure gauge on the dash like the SD does? What was happening with my truck was that when I cold started it, it would run for a bit and the oil pressure gauge would never come up. Then when I restarted, it would jump up and the truck would run fine. Sometimes (new oil, not that cold) it would start, run for a few and then stumble like it was going to die and then the oil pressure gauge would jump up and the RPMs would as well and the truck would run fine. If you have an oil pressure gauge on the dash, watch it when you are cold starting.

If sucking air into the fuel lines at startup was your problem, it would be even more pronounced under load. Your fuel demand is not that high to start the truck. You would notice even bigger problems under load when the fuel demand is higher.


Change that for sure. And while you are at it, take the opportunity to clean the tube that runs from the sensor to the pass side manifold. Welcome to guzzle's Exhaust Backpressure Sensor Cleaning Maintenance Web Page

 

I'd like to know how you tested the LPO without a mechanical gauge? The Factory sender is not a pressure sender, just a pressure switch.

If your injector sleeves were bad you would have fuel in your coolant.

Whats your duty cycle when cranking.

 

I did use a mechanical guage, sorry i didnt mention that, but i checked cranking pressure by unhooking the valve cover harnesses, and just cranked it over when the engine was cold. hooked the covers back up and ran it, pressure is fine...

im not talking about injector sleeves, im talking about the connections where the fuel lines meet the back of the heads.

I didnt look at the duty cycle when i had the scanner hooked up, will post next time i have the opportunity.

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see the oil in this motor right now has approx 6k on it (i know im about a thousand over, shame on me). but it has been warmer the past couple days, and the problem has vanished. but when the problem was present, the guage would jump up to the high side of "normal" pressure, the truck would die, loose pressure, and once it re-started the pressure went back to normal...

 

Tech files are wrong. They are huei injectors THEY RUN AND ARE OPERATED BY HIGH PRESSURE OIL!!!!! if. U got a bad pump in the sump ur not gonna have any oil feeding the hpop sounds like u might have some blockage?! Maybe old engine oil sludgebin the screen in the pump. Just tryin to help out

 

see what my whole deal with the oil is, is that even with 6k on it, it hasnt even turned color yet. i can drain the oil right now and its absolutely clean, like no joke, looks like it came out of the 5 gallon pale. also, if the primary oil pump was worn out of spec, when the engine oil gets warmer, viscosity drops, so in turn i would have less pressure and the problem would be ALOT more noticable. but....... i am thinking of changing the pump anyway at 300k (4k away), ford says i have to remove the oil pan, and others tell me just the radiator, fan, pulley, harmonic balancer, and front crank seal. can anyone tell me whats actually involved?

also ford has an o-ring kit for the fuel lines that connect to the rear of the cylinder heads, so ill knock those out while im at it.

and does anyone know where i can find an EBPV sensor for less than $100? thats what ford's asking and i think thats a little high.