it's scary what can be found in an ECM

triton

triton

Scarlet Fever
I wanted to post up what I found in a friends truck. It's a 06 mega cab he just bought. Said it ran great and has lots of power. I showed the tune to others who agreed something was definitely done to the truck. The dealer nor the new owner have a clue what it could have been though

I'm not pointing at any tuners out there, only wanting to show why when we run some programming, it can help to ruin, injectors and/or melt down a truck.

This is just the fuel psi table. Had the stock limiters not been in place, it wouldn't have taken long to blow out a set of injectors ! The timing and other tables look as bad.

Ohmy.jpg
 
no but, 36K psi sure is ! Point is, you just don't know what's in there until you have the ability to look
 
LReiff said:
Cool! How was the throttle hang?
Click to expand...


I'll have to ask him if there was any.... you'd think ! He's only had the truck a few weeks and because of it's power, thought there might be something done.

There's no telling what tuner, box or custom did that but, it's extreme to say the least !
 
Last edited:
Aftermarket tuners and genius engineers at Cummins are the reasons these trucks melt and waste injectors. The factory tables look ridiculous too only the tables don't command such high parameters.
 
ComnRailPwr said:
Aftermarket tuners and genius engineers at Cummins are the reasons these trucks melt and waste injectors. The factory tables look ridiculous too only the tables don't command such high parameters.
Click to expand...

Why is it the guys that play with them know more about how the chit works and how to make it stay together?
 
ComnRailPwr said:
Aftermarket tuners and genius engineers at Cummins are the reasons these trucks melt and waste injectors. The factory tables look ridiculous too only the tables don't command such high parameters.
Click to expand...

As it was pointed out to me, the factory tables do look pretty bad BUT, they had to be designed for the truck to be drivable in all kinds of conditions...i,e......drive through the Swiss Alps when it's 10* @ 10,000ft. or through death valley at 110*

We're looking for specific tuning which is why we can adjust for our driving conditions alone
 
Yup, whoever's tune that was is lucky there is a rail pressure limiter in the ECM.

This is also why you need the ability to data log.

You can tell the ECM to do whatever you want, it doesn't mean it's going to do it.

There are dozens of limiters in the ECM and the rail pressure is just one of them.

In this case, that limiter was still set to 23,205 psi, while the tune was asking for 36k+ psi.

This is what tuning in the blind does. You put in some made up number and you do that until you get an outcome. Normally that outcome is achieved due to values being raised in lower parts of the map than they need to be. This results in poor drivability and generally bad habits from the motor.
 
Last edited:
That table wouldn't drive nearly as bad as it looks. That 36k is meaningless, obviously it has had a tuner on it and sad to say sometimes they just use a high figure to lock it to the limiter.
 
I have seen this file before and it does drive ok, but the truck has terrible rail rattle and it only amplifies the throttle hang when run on an 06.
 
Actually, the 36k is NOT meaningless.

It would be meaningless if it was there only at elevated RPM's and throttle conditions, but its not. The pressure demand extends all the way down into the areas that have no demand for fuel. THIS is what causes the rail hang.

Even though the throttle is being lifted, the ECM is still calling for max pressure.

True, its only going to be 23,205 psi, but its calling for it when you're not.

Thats garbage tuning. There is no reason to put in that kind of figure to get the pressure you want.

Its no different then calling for 38 degrees of timing when the limiter is 25.

Again, this where the data log comes in. You may be calling for X degrees of timing, but unless you can see it, you have no idea what its actually doing.
 
You must log in or register to reply here.
Back
Top