ECM Memory

[LEPage]

Can anyone tell me for sure if the computer on these things records high boost/egt, and if a Powermax CR and or Edge EZ leave anything on it? Thanks.

 

[SP Diesel]

If they are behaving correctly they should not leave a trace on the ECU. The TST has been known to blip every once and a while and throw some codes.



Those codes could be used against you by a dealer, but if you are able to go to an autoparts store before heading to the dealer they could clear any codes for you.

 

[mattymac]

theres no way for EGT's to be recorded by the ecm, theres no thermocoupler/sensor installed from factory, as for boost goes as SP said, if they are doing what they are supposed to it sends a "fooled" value to the ecm that keeps things happy, if not you will get a check engine light on for overboost.

 

[Prairie Dog]

As I understand it, (and I could be wrong) the TST always shows the cpu the same boost level, at least with the 03's. Which would look kinda fishy if someone actually looked at a history of boost values.

 

[cerberusiam]

I believe there is a certain amount of freeze frame data that is stored, both in relationship to codes and on a timed basis. Haven't been able to verify the timing or vaidity of the latter but pretty sure on the codes.

 

[Bob4x4]

We do have freeze frame data available



Bob

 

[LEPage]

Forgive my syupidity, but what do yoy mean by freeze frame?

 

[Bob Wagner]

Forgive my syupidity, but what do yoy mean by freeze frame?

The service industry calls the Check Engine light on your dash an "MIL" or Malfunction Indicator Light. It shows three different types of signals. Occasional flashes show momentary malfunctions. It stays on if the problem is of a more serious nature, affecting the emissions output or safety of the vehicle. A constantly flashing MIL is a sign of a major problem which can cause serious damage if the engine is not stopped immediately. In all cases a "freeze frame" of all sensor readings at the time is recorded in the central computer of the vehicle



Hard failure signals caused by serious problems will cause the MIL to stay on any time the car is running until the problem is repaired and the MIL reset. Intermittent failures cause the MIL to light momentarily and they often go out before the problem is located. The freeze frame of the car's condition captured in the computer at the time of the malfunction can be very valuable in diagnosing these intermittent problems. However, in some cases if the car completes three driving cycles without a re-occurrence of the problem, the freeze frame will be erased.

 

[LMcCary]

You can not erase logged code events without a pasword from cummins or ma chrysler. So if the ECM sets infomation to memory, it is for all practical purposes, permanent unless removed by the dealer.

 

[zstroken]

Unless the boxes perform a linear modification of the boost signal, don't you think the tech will wonder why you have the same boost at say 1800 rpm as you do at 3600. I have been told by a reliable source that the cummins ECM tracks a huge amount of data. Most of the techs don't even know how to get it. 5 star tells them how to get the file and has it sent to them for them to run through the ringer.

 

[LMcCary]

zstroken, you are right. the logged events that are at their limits at the wrong time or too often give the dealer reason to flag your truck as a abused or tamered with vehicle. Most of the time they use three or more of these events that are set to void your warranty because in the real world there is no way these events would take place.

 

[Andersonville]

Its not a Cummins ECM, it is a STAR ECM. The Cummins ECM would be

MUCH better. Cummins scan tool cant get into the ECM or so I have been told. Just my . 02