Engine/Transmission (1998.5 - 2002) Did my ECM croak??

[kdunham]

I'm using a Genisys scanner and it'll let me into OBD2 mode but not OEM mode,no matter what,I've tried everything. I have the correct chip in the scanner for OEM mode and the connections are fine,it works perfect in OBD2. Did my ECM just take a *****?? It'll also set a grid heater b code(I have a new grid heater,it set the code before too) and an overboost code,all I have is a larger exhaust,K&N filter and 300 injectors. I have to stomp it pretty hard for the overboost code but it has a new MAP sensor and it shows up to 75iHG on the scanner,which I believe translates into around 18 lbs of boost,someone fine tune those figures if they're off. Also,what is the IAT failure rate? I've cleaned mine off before but according to one of Marco's articles from somewhere else it can still be out of range or not responsive enough,causing a weird or late fuel curve. Thanks...

 

[ToolManTimTaylor]

With a k&n and bosch 300's and 4" sure betchya the ecm is defueling. The reason you are seeing 18 is because the truck is defueling. It does it so fast to knock the fuel down to keep it under 20Lbs of boost and it does it so quick that it keeps it down because it can determine rpm increase in time VS Pedal position and Map Sensor. The IAT simply gets dirty from oiled filters (Your Kill & Nuke filter lets alot of ftuff thru it as well as oil) and in a sense insulates the tip providing a false reading. Failure rates I am not sure of but Yes it can make a difference in fuel curve. I have had an IAT strapped in the enine bay away from heat (Grounded too) and in the summer I could tell a difference in the "Snap" if you will of the throttle between the two.



Not all scanners can pickup the codes BTW and are preloaded (Weather on laptop or hanheld) with a generic OEM OBDII code dtatabase to draw from. Double check your findings at an autozone where they will scan for free.

 

[rattlnrench]

I had the same problem with my Genysis untill I got the Pathfinder 2002 software. Another "Chip" came with it too. Pathfinder 1999 or 2000 will not work on the Cummins & OTC knows it. I went around & around with them for almost 2 years before mine was right & only after the latest software was installed. I doubt that Autozone can read JTEC or Cummins Engine controller like the OTC can when it's right. I'm sure they can do OBDII. You're already getting that now. If you don't have the latest software that is probably your problem unless the software is corrupted. If you have the right Smartcard you can download updates off the Genysis website. Good Luck.