Pull that ebpv sensor and clean it at the very least. Clean the tube. Heck id even try driving it with the ebpv plug disconnected at the pedistal. With a sooted up tube the pcm is detecting no back pressure and may not be opening up your flapper on exhuast side of turbo, giving you the "idleing along" feeling when flooring it. Had it stick on my truck at WOT situations with a plugged up tube and sensor , making my truck a dog. Litteraly wouldnt get out of its own way.

If temps are below 50 all winter long where you live get 5w40 and stick with it all winter long, (summer to if you prefer). Run a good additive religiously starting now. ULSD will play games with your mind sometimes creating a "wandering idle" situation in my truck, making you think you have problems brewingin that engine . I swear by stanadyne. Cant think of anything else to get your romping cured , right now. Set a good baseline with your truck by treating your fuel and using that 5w40 oil. just thought of this: BOB, BOB BOB, get it done now!

 

I havent read every post in this trhead but I get the jist of it.

You are wasting your time and money without running some tests with a scanner. Here is what tests you need to run when cold,

Buzz test, listen to the inj's as they buzz, listen for different sounding injs or some that sound faint.

Check all the sensor readings like EOT, IAT, MAP, etc and make sure readings jive with what they should be reading, Ex. eot should not read 200+ degrees on startup.

Check ICP PSI and %duty cycle at idle and at wot when cold and when hot, also watch for anything screwy like the pressure spiking up and down along with the romp or if it stays flat.

IMO with what I have gathered from your post you have a injection oil problem, could be IPR, I suspect injs. If when you run the buzz and the injs sound faint and not loud and crisp then the poppet valves are worn out in the injs. This will cause hard cold starting, low power and a miss until completly warmed up.

Dont give up but dont just throw parts at it either, need to narrow down the symptoms then go from there.

 

Everyone thanks.

I have cleaned the EBPV tube/sensor and just recently plugged it back in. It romped with it unplugged too.

I don't have a way to check fuel pressure. I'd have to buy the adapter or kit from one of the vendors on here.

Does a shop need to do the buzz test on the injectors, etc... what can I do at home versus what needs to be done at the shop?

I hate to throw more money at it, but I'll probably stick it in the shop Tuesday...

 

I think a Predator will run a buzz but I am not sure. But yes a competent shop will be able to run a buzz.

Where are yu located?

 

I'm in New Orleans, LA. A friend recommended a good guy nearby to bring it to. My dad has done business with him as well. He's a good guy to deal with so I feel comfortable bring it into him. He has also just finished some PSD training stuff too...

 

Beans, you beat me to it. The earlier posts suggesting glow plugs are way off track for this incident.
The romping after startup is purely an engine managment problem. What that is I cannot say because I don't know, no experience on my part.
But the glow plugs ONLY JOB is to generate enough heat in the cylinders to get the injected fuel to ignite. Once that is accomplished and the engine is running, they are no longer relevent. The only difference they will make is help reduce smoke at idle on a cold engine.

 

John, Beans is right we do need to get this hooked up.

I am still wondering if 12V is getting to the GP's. Check voltage from the large post to batt negative. One will always be hot, one will only show voltage if the PCM has commanded the GP's on. A bad EOT sensor will cause the PCM not to command the GP's because it will use a default of 212*F in the absence on an EOT signal.

Another possibility if a Left/Right bank ICP balance fault and will take mechanical gauges to determine this. (Cold Oil could be a factor)

Fuel pressure is also a possibility but again mechanical gauges are needed.

When you posted the ohm test results you said one side tested at 6.0 ohms. this is a little high and unusuall for all injectors to ohm the exact same?

If the diablo can read sensors Check IAT and EOT they should be within 11* of each other on an uncranked engine after sitting overnight and within 5.4* of local temps.

Check EBP sensor, Baro, and MAP they should read within 1.5psi of local atmospheric pressure. Keep in mind that the weather channles 29.97 is in MM/Hg and would be equal to 14.7 psi.

Looking at EBP the pressure at WOT should not excede 34psi.

Also if it can, run KOEO, KOER, Buzz, and CCT and let us know what it finds.

 

My Diablo is able to read all of the above. It cannot do buzz tests.
It's quite a versatile tool if you know how to use it.

 

Also John if you want the complete pinpoint test we have been jumping through PM me your email address and I'll send it to you.

 

Guys,

Exactly what is the "buzz test"? Does it just actuate the injector solenoid and measure the current draw then determine if it's good or bad? Is it a fixed voltage that is firing the injector or a PWM signal (pulse width modulation)?

I'm trying to line up the Predator right now. My buddy's out fishing right now. Gotta love South Louisiana. You can go fishing nearly anywhere and still get cell phone reception!

Alan, I'll have to say the GP's are functional. With the key off I have 12.xx volts on the hot side of the GPR. Turn the key on and I have around 11.xx volts on the output side going to the GP's. So, I'd say they're working fine now. This was the first thing I checked before I cranked it up.

When I checked the GP's and injectors last week with the DVM I posted the highest reading of each bank. According to what everyone said I think that tested OK.

Also, what exactly is Beans describing when he said this>>

Does this mean the that the injector spray pattern is basically bad and then it improves as the poppet valves heat up and expand. Is this correct? Or does it mean the poppet valves are sticking/binding from the cold? Or does this mean I have a bad IPR? I'm just trying to understand all of this in my head.

Even when the truck is hot it still has a slight roughness and loudness to it that other 7.3's don't have. So, maybe It's an injector problem.

I have noticed this though. I recently made a road trip to Dallas/Southern Oklahoma from New Orleans and back. We only stopped for fuel so the highway runs were long. When I would pull in to a truck stop I noticed the truck was running smoother, but after driving around in the stop and go traffic for a fe wminutes it got a little rought/louder. What does this sound like?

My truck has never did the white smoke on startup even when it got down in the high 20's a few weeks back. So, I would say the GP system is not the culprit. It's got to be the fuel/oil/injector side of things. I'll let you guys know when I get that Predator in my hands. Should be later today. Don't know how much time I'll be able to mess with the truck though since today is hectic around the house and company is coming over tomorrow.

I'll definitely keep you guys posted. I appreciate everyone's help. I wish all of you guys a Merry Christmas and a Happy New Year.

 

That GP system sounds fine.

When an injector poppet sitcks open it allows oil to free flow through the injector http://www.intellidog.com/dieselmann/injector.htm
That is one of the pinpoints.

Email on the way John

Kwikkordead has a diablo predator so if you need specific user help I am sure he can provide it for the

 

The buzz accuates each injector in sequence 1-8 and wll sense resistance or open circuit. In this case ignore the test outcoem, more then likely it will pass, you have to listen to each inj, a weak sounding inj will indicate a messed up poppet valve or armeture plate.

When the valve wears the space under the armeture plate decreases until it will bottom out and nolonger hold a good seal at the valve seat. This come apparent at cold start up because the metal will be its smallest when cold, as teh engine warms the metal will ever so slightly expand making the seal, we are talking as much as .0001 will make a differance here.

The IPR could be slightly stuck causing issues also, it can be pulled and cleaned as well as orings replaced to rule it out.

 

Thanks beans.....

 

John, If that passenger side injector is still reading > 5 Ohms after replacing the harness. I think we are zeroing in on the proble. I emailed you pinpoint test NA to help isolate the problem.

 

Sorry to drop that compression thing like that and sign off but I had to go to bed. 12 hour days can suck when you're up too late.

Here is my thinking process: I believe you are getting fuel and your glow plugs are working based on what you have posted. I also do not believe a PSD will start and romp without that fuel supply. Since it seems like all of that is in order, it would appear to me that there is insufficient compression to burn the fuel, at least at first until something happens. That something happenning is what we need to figure out more so than what is not happenning if this makes sense.

I sincerely hope I am wrong. Also, perhaps Amiller can find something for you and I too will learn something. I would agree at this point to stop throwing parts at it and have it properly diagnosed. That intellidog link posted previously by Amiller is chock full of great info. I would spend some quality time there. Again, hope you find something simple and Merry Christmas, as best it can be under the circumstances.