I recently inherited my fathers 2007 2500 6.7 cummins.
I got it with no catalytic converter (straight pipe) and the egr cooler, valves and exhaust brake have all been removed. It looked like he did a complete h&s delete kit.
however someone removed the tuner prior to me receiving it.

When I drive, it will run about 15 feet and throw a low/weak fuel pressure code and goes into safe mode "limp mode". I took it to a diesel mechanic who said the programming in the computer was unreadable. we took it to the dealer who reset the computer back to default. Then I purchased an autocal but when the mechanic installed it nothing changed. we are still getting the same code and limp mode. We are both frustrated and I am running out of time. I don't want to keep the truck and will be deploying to Afghanistan at the end of the year. so I need to get it fixed and sold soon.
I have never dealt with anything like this before and I am not a mechanic.

Please help?

 

I am wondering why you purchased an autocal when you need a programmer like Smarty, H&S or Raceme that will do the deletes your truck already has installed?

 

I contacted h&s and they would not sell me a programmer unless I got EPA approval first. I then researched based on what little knowledge I have and contacted several people who directed me to anarchy diesel. the recommended the autocal and so did two other companies. but anarchy actually returned my phone calls, talked to the mechanic and answered my questions.

Anarchy is working with the mechanic to write another tune as we speak.
I wondered if it was the wrong tune. Do you have any suggestions for me?

thanks

 

It sounds like someone had access to the truck and may have done more than just remove the tune.
Is the low fuel supply pressure real? Did the mechanic check?
Lots of things to check in the fuel system if the code is real, including a corrupted ecm.
The truck should run like crap on a stock tune and deletes, but it will run. It will just throw a bunch of emissions codes and blow some white smoke.
Did the dealer say the flash was successful and the ecm functioning normally?
Or did they just do the flash and hand it back to you? That would be a good question to ask them.

 

So I talked with the mechanic again to verify the info given to me prior.

The Dealer cleared the codes on the ECU and said it had been altered from factory specs. The dealer did not put it back to manufacturer default. The dealer said the truck is going into "limp mode" after 1500 RPMs because the ECU is seeing all the emmissions equipment gone and forcing the "limp mode". Of course, the dealer said to put all the emmissions equipment back on the truck...Not going to happen!

However, I thought the autocal would override any programming in the ECU even if it was messed up. Is this true? Or will it only override the factory default programming?

Is it possible the ECU needs to be replaced (corrupt)?
How do we test the ECU for corruption?
I don't have a problem replacing it because I don't have any money into the vehicle anyway and I don't want to pass a lemon onto the next owner. I want it done right while keeping the performance / mpg.

I appreciate the help, thanks.

 

Ok, that explains alot. Pass this info on to your tuner. If the efi autocal can't overwrite the tune then he should be able to send you a clean factory file to overwrite it. If not then the dealer can flash the stock tune on it. From there you can load the autocal an see what happens.
If it won't accept the stock tune then the dealer can make that call.
Efi can be written for a stock truck or for emissions delete. Best to verify you have a delete tune.
Yes, efi delete tune blocks the codes and limp mode although I'm suspicious of the low fuel pressure code. You should tackle one thing at a time. Get the correct delete tune loaded and see if the emissions codes are gone. If so then see if you get the fuel code and limp mode. If it comes back then I doubt its due to the tune or deletes.

 

XCC
you were right, the reset the ECM to factory default and the autocal worked.

Now there is no engine check lights and ECM works fine.

And the fuel pressure issue is still there (limp mode). But with no codes or check engine lights.

Talking with several mechanics, I am fairly certain it is the fuel injectors because:

1.The fuel level was sitting on empty for a while before I picked it up and is still on empty.

2.The fuel filter was filthy and needed to be replaced.

The mechanic decided to fill the tank with diesel and injector cleaner and let it run for a while to try and clean the system out. Hopefully I will have good news on Monday.
Again, the truck would go in limp mode around 30-35 mph and not give more power to accelerate. when the mechanic monitored the fuel pressure, it was reading high pressure at high pressure at low RPMs and lower pressure at higher RPMs.

Again, any advise is greatly appreciated.
What do you think?

thanks again

 

Glad to hear it. Just gotta tackle one issue at a time.
Before you jump on injectors you should be checking everything fuel supply related. 4-5k lbs on the rail pressure at idle is normal, high rpm rail pressure is dependent on the engine load. Flat ground, 65mph for me is around 10-11k.
If its hitting limp mode under heavy throttle then the fprv is suspect. That can give you low rail pressure at high engine load. But so can a bad lift pump, fca, cp3 etc. All a lot cheaper than new injectors.
So start eliminating things from the tank forward and if you end up at the injectors, so be it.
Hopefully the injector cleaner helps.