cat dyno results

AJMB: Two pieces missing that I need to help. One being how much HP is lost between rated RPM. Most times the 1800 rated engine has a higher torque setting then does the 2100 rated engine. Have a CAT person check to see if you have the highest torque available for the 1800 rated engine. You don't need RPM for good fuel mileage you need torque which is rated at the bottom number. If you lose more than 30 HP between the 1800 rated RPM and 1500 then a possible cause that I have dealt with in many CATS and Cummins is that the exhaust valve adjustment is .001-.003 thousands too tight, and when the engine gets hot, the valve adjustment gets tighter and then it causes a higher than normal HP loss on pull down results and thereby making the driver run engine harder to meet expected speed. If you have high mileage on the injectors you can raise fuel rates as high as you want but if the holes in the injectors are plugged you won't get any better results. I am assuming this is a 500HP rated engine and if the valve and jake adjustments are too tight it will make it run like a 350. Good luck.

 

I've given up on getting much help from a Cat dealer unless the problem slaps them in the face.

Hang out here a while ...you'll find your help.

 

there's 29 hp difference between 1796 and 1500.

It's an ACERT, you can't get good fuel mileage without doing some "illegal" changes.

 

Are the tires 22 low pro or full size 22.5s?

 

Mr. Haney and others will be along and get you where you need to be.
As Paul said, i wouldnt count on Cat for much(except for taking your $).
and welcome to the forum...

 

I was having trouble with the mpgs on my acert here the last few weeks. The other day it started to derate at 1500 and the check engine light would come on. Took it to CAT and they said I had a bad IVA told me which one. My mileage is back up where it ought to be. So apparantly a IVA going bad can hurt your mpgs.

ajmb I would have husband check the exhaust manifold very closely for leaks. Check the expansion joints. Any leakage will hurt mileage a great deal. When I started out with my ACERT it would only get in the low 5s now it gets 6.5 pretty consistantly and it runs great. It could get better mileage wise but I have a heavy foot. So there is hope but it sounds as if there might be a problem that needs fixed before you make other mods.

 

The Acert engine in stock form isn't known to get good fuel mileage. Are you saying that your husband pulls two trailers? I find that the harder the work load is over time the worse the fuel mileage is with an Acert engine.

The best way to help fuel mileage is to flash the ECM with a modified flash file. I've done a number of these in the past with very good results. With your fuel mileage being this low usually the fuel mileage increases after the flash are in the 0.5 mpg range and higher depending on how you'd like the ECM tuned. I've had a number of other members do the tuning of the ECM on the Acert with great fuel mileage increases, if your interested you can PM