Engine/Transmission (1998.5 - 2002) What happens if you set an overboost code?

[HC]

Numerous posts have said leaving a boost elbow on while removing your EZ or other box may result in setting an "overboost" code. Does this effect engine performance in any way, or just leave a diagnostic code in the computer?

My truck is now out of warranty, so I really don't care any more what codes are stored in the computer, but if this is going to put me in "limp mode", or ruin performance and force a return to the dealer for reset, then I will be more carefull...

 

[Mr. Brewski]

Mine set an overboost coade a few years back when I was fooling around with a PE box. I was able to clear the code with a friends fancy Snap-On OBDII scanner. You can find cheaper scanners at Sears that will clear the PCM codes, but codes in the ECM are there unless you have a Cummins scanner. When it set the code, it didnt go into limp mode if I remember correctly.

 

[KatDiesel]

Overboost code is just a code.



It will not put you into limp mode or anything.



Basically it won't hurt a thing... ..... however it will defuel when it sees too much boost... . you'll feel it pulling the fuel back.



I ran without any kinda of boost module for about a week or so just for the hell of it with my DDIII's (out of curiosity), and the defueling was really noticable in my case. Wastegate was set for around 35psi..... but with the defueling I couldn't build much over 30psi.



You don't list if you have injectors... ... .

 

[HC]

275 RV injectors were installed two days ago, EZ and boost elbow a few weeks before that. Was thinking about running for a few days with just the injectors to see how she runs and where mpg and EGT's are with only the injectors...

I'll update the signature soon...

 

[TowPro]

Bet you find the EGT's go up without the EZ. The boost module part of the EZ helps with EGT's as well as the timing part.

Originally posted by HC

275 RV injectors were installed two days ago, EZ and boost elbow a few weeks before that. Was thinking about running for a few days with just the injectors to see how she runs and where mpg and EGT's are with only the injectors...

I'll update the signature soon...