ISX 2350 485

[Rawze]

(02-01-2017 )zare6 Wrote:  One more thing as far as the ecm is concerned, I ordered this truck new so nobody touched the ecm, and I own 3 others with cats, the trucks work side by side and I monitor the fuel mileage daily, my cats used 40 to 50 litres a day more for the first 100000 miles or so, now the cummins is using 20 to 40 litres ( 5 to 10 gallons)

You cannot compare boost and other reading from cat to cummins 2350. Engines are totally different including compression ratios, fueling, boost, everything, literally.

===

I have seen a few 2350 engines boost up to 38-lbs. Even a couple that did it new from the factory. It is actually not normal and is too high for them. It should peak around 32-33 max, but the OEM shops will ignore it because it does not throw a CEL.

Too high boost (or low) can be caused by many different things, including NOx sensors and emissions system components. Usually though, it is caused by the IMAP, exhaust back-pressure, and/EGR differential pressure sensor not reading correctly. It can also be caused by the Altitude sensor reading incorrectly, and it thinks you are at a higher altitude, and need more oxygen in the cylinders.

It can also be from the wrong program in it, and don't think for a minute that just because no one has touched it but the stealership, that it could not have been altered. I have seen it plenty. -- It also may simply be that the ECM has an out of date file that is causing over-boost, and it needs an update.


-- Your biggest mistake so far is the fact that you keep taking it to morons (OEM stealerships). Keep doing that and you will eventually end like all the rest of the guys who fail at trucking, or are completely broke all the damn time, tens of thousands in lost revenue while they guess at your problems over and over.

===

Throw that warranty in the trash can, go make an appointment wit Mr. Hag's shop, gearheads shop, or with Unilevers and never look back while you still have a good chance towards turning it into a decent engine.