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put new DAP injectors in last summer. Have been fighting High EGTs and black smoke since. Didn't think +50 injectors would cause this much trouble. MAP 48 when pulling hard. Is  there ANYTHING in the VP44 that can make it overfuel with no codes? 

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  • Quadzilla Power
    Quadzilla Power

    I think there was a miscommunication. Adding fuel won't drop EGTs, but adjusting the timing will. Honestly though, those are some really high EGTs and I'm not sure that a tuner only will fix your issu

  • Mopar1973Man
    Mopar1973Man

    The only thing that I have seen happen on our turbos is the bearings get worn out and the oil weeps in on the compressor side. Beyond that then I would build a boost test cap for the mouth of the turb

  • Mopar1973Man
    Mopar1973Man

    I think we all agree to a possible boost right gang? 

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I have DAP 50's in mine and they are a bit smokey until the trubo spools. Sounds like your waste gate is stuck closed. That would explain the 48 psi on the map and high egt's. But if you are stock you should be getting an over boost code at the least. Can you give us some more info on your truck. Is it stock or what have you. Anything you changed or added.

 

Jack, I have been kidded about running a lot bio diesel in mine but I dont think I have ever seen anyone with such a wide range of fuels they have run thru there Cummins.

  • Author

Hahaha! The fuel has been on long experiment. I always run at least 80% WVO. I cut it in the winter depending on temp. My VP has 230,000. The smoke didn't bother me too much but when I started pulling the race trailer this spring I noticed the EGTs climbing fast. I wonder if the turbo is worn out IE wont spool fast enough? 

 

If you have a stock HX35 in there it should not go over about 20psi unless you have boost elbow of something else to keep the gate closed. Once you get over about 35psi you are out of the turbos range of efficiency. 48 psi on that turbo will crank up the egts. There folks here that know way more about this than I do. My HX has a waste that opens around 34 psi and my Comp tuner does the boost fooling to the ECM. Have you done anything extra to the truck or is it still stock?

 

That is very good mileage on the VP. I have 234k on mine. I feed mine a good bit of bio diesel in the past 4 or 5 years and the other 4 or 5 years #2 diesel with 2 cycle oil at about 1 oz per gallon. I recognize every thing in your fuel list except RUG??

  • Author

Yep, stock turbo. I was reading the MAP from a code reader under various loads. I thank the actual boost is 15 below MAP. I cleaned the waste gate but that didn't seem to change anything. I did not check to see if the accuator worked.

 

When I say stock I dont mean just the turbo, I mean anything you have done to improve performance. If you look below this post you can see what I have added to mine. I you have owned since new and not added anything it is stock.

 

You can put air pressure to the actuator and see if opens. 20 psi or so is all it should take for stock actuator. Some scanners do not read the MAP pressure right. My scan gauge reads idle on mine at around 25 psi and about 39 at WOT. I do have a mechanical gauge on mine and 32 is about the top for me right now. It can get hot pretty quick with the tuner turned up. By then I am going faster than I should. 

I’d get a dedicated set of gauges, map readings for boost are real iffy. 

 

Being a 99 you should have an HX regardless of manual or auto and like Dripley stated, about 35lbs is all its good for so anything well above or below that can cause you’re high egt issues. 50hp injectors shouldn’t be too much for the HX to handle but if it’s all original with that many miles it’s definitely possible it needs some attention.

 

Either way I say run an actual boost gauge (and fuel pressure if you don’t already have it!) and since you’re saying you have high EGTs I’m assuming you already have that gauge.

 

Although before we start adding gauges, what are the temps you’re seeing EGT wise?? 

  • Author

Fuel pressure is never less that 20. No trailer, 75 mph 900 -1000. Loaded, it well peg a 1600 gauge but I can usually keep it around 1200 if I drive VERY carefully. No difference between Diesel and home brew. 10 MPG loaded. 18 - 20 unloaded. Water temps never exceed 190. I know, the home brew scares everyone BUT, it's close to 20,000 gallons of diesel that I have not purchased. Thanks for the ideas.

Yea 1600 is getting pretty toasty, I’d say get a dedicated boost gauge to verify what your boost numbers are and then we can go from there.

 

Either way you shouldn’t have issues controlling those injectors. It might be as simple a fix as a boost elbow and fooler or just a boost leak.

High egt’s and black smoke, I would start checking for boost leaks. 

 

I run 75hp injectors on a stock truck, no electronics, and also have a stuck wastegate. 

 

No black smoke, egts don’t go above 900, and I hit 33lbs boost. 

 

I would look look into a boost leak of some sorts.  

Edited by Ben

  • Owner

The only thing that I have seen happen on our turbos is the bearings get worn out and the oil weeps in on the compressor side. Beyond that then I would build a boost test cap for the mouth of the turbo and pressurize the system then look for boost leaks. If you losing to much boost the EGT's will rise out of control fast. Now if you have no boost & fuel management from like a tuner then you are going to be hung up with the limits of the ECM. Most of us are running a tuner like Edge or Quadzilla to manage boost and fuel at the bare minimum. 

 

Like myself, I'm running +75HP injectors, HX35/40 Hybrid turbo, and Quadzilla Adrenaline. I can turn down to just CANBus fuel (no wiretap) and I can floor it and never smoke or even get crazy hot. I'm going to be towing here in the next few days and I'll report the results. The short haul to town and back climbing the canyon I could kick that pig and never worry about EGT's. 

 

<- (Check out my garage look up my RV)

Edited by Mopar1973Man

1600* is pretty high for 50HP injectors.  Have you verified your EGT gauge and probe are accurate?  If its grounding out or failing from some other cause it can change EGT readings significantly.

  • Author

Alright! Got some real time data. Boost gauge attached. Rolled into it as hard as I dared. Boost was 24, EGT was 1500, and MAP from code scanner was 72! 

I have a quad with V2 tuning and I'm able to watch it live, not sure if you were able to do so

Edit, this will be able to tell you also

https://www.google.com/search?q=obdlink+mx&amp;oq=obdli&amp;aqs=chrome.1.69i57j0l3.8612j0j4&amp;client=ms-android-verizon&amp;sourceid=chrome-mobile&amp;ie=UTF-8

 

And you're not pushing that much boost anyway you ever have a bad sensor on a short somewhere

Edited by Dieselfuture

  • Author

Yep. Real time. What are the units of measurement for the MAP?

5 minutes ago, Jack Owen said:

Yep. Real time. What are the units of measurement for the MAP?

 On my cts2 the map units are psi.  

 

My map values are 15lbs higher than the boost psi.  

 

The obd boost reading and my boost gauge are identical.  

Doesn't seem like a MAP issue to me. 24lbs is on the high end of a normal HX without boost elbow and fooler, I think if you added those you'd see roughly another 10lbs of boost and cool things off. Still suprising you're getting so warm with 50hp sticks.