ISX cm2350 low. power/poor. Fuel milage.

[DPS567180]

(02-26-2025 )Rawze Wrote:  

(02-26-2025 )DPS567180 Wrote:  What can I do to correct that? Is it a programming issue or a mechanical issue?

== ensure your egr valve is not hanging open.

== ensure your intake throttle valve is not hanging open.

== stop driving it below 1500 all the time and lugging it to death. Below 1500 is the bottom 1/3 of the working range of that engine. That engine can run at 2100+rpm for the next million miles, and it will not hurt it. The 1650 -1750 rpm range is the center-point of its operating zones, where it lasts its longest.

There is a plague of trucks out there that are geared waaay too tall for their application. Also, Auto-shifter trannies are programmed to luge these engine to death these days too. - Its been a problems now for about 10+ years, and only getting worse. - Personally, it seems that by advertising they can run that low rpm, the engine makers are somewhat trying to make the engines last only long enough for the warranty to expire? .. but that is just my own thoughts.

I will pay more attention to my habits Check EGR valve and see if that changes anything. It seems I can't get above 1500rpm no matter what I do. Also this is an old Swift truck 400 ST. Are there any settings and insite that I might want to look at to make sure that fleet programming doesn't have any limited?