2006 peterbilt 379 with acert motor having power issues

That sensor is a common failure. It is on the right side of the motor right next to the first valve cover. The big solinoid is not what your looking for it is the one next to that solinoid standing straight up next to valve cover. Unplug it take it loose with a socket put a new o-ring on the threads tighten it up plug in and your good.

 

Sounds like the harness or actuator. When the harness on my Acert gave out, it struggled to get to 55. Yet, once I got it to highway speed, all was good. It would jerk all kinds of crazy b4 it smoothed out. You will get a "bad injector" code. I moved injectors around in order to see if the code followed the injector(s) due to the common power per 2 cylinders. It takes a few good steady hours to swap out the harness. There are a few discussions on the Acert injector harness when you do the search.

 

Intake actuation pressure sensor is the cause of that flash code 95% of the time. It could also be wiring or a few other things. I'd replace the sensor. In the slim chance that it's not the sensor, you'll have a spare on hand, it wont go to waste, they do fail.

 

You need to see what the code is first!!! It could be just a bad iva ( intake valve actuator) and the engine has went into limp mode meaning it probably has cut power by maybe 25% or maybe more!!! Also there is not a egr valve on these motors.

 

To view engine codes= turn cruise switch to off then hold the set/resume switch to either position until the engine light lamp begins to flash then release the switch. The lamp will then flash the first digit of the code and will pause for a second the flash the second digit of the code I have the factory service manual with me all the time so if you get the codes post them and I or someone else can tell you what they mean.

 

Merged them for you.

 

Gear head and grape ape nailed it.
Should be around $140 for the pressure sending unit. Front passenger side , top of the motor, kinda like a big spark plug with a harness ( 2 wire I think ) plugged into it. Screws in vertically.
You need a tiny little o-ring also.
Very simple job, you'll only leak a few drops of oil.
%95 that this is your problem but it shouldn't derate your motor so I'd definitely pick up some filters while your at it... sounds like your fuel filter is screaming at you...

Also shouldn't cause any damage if you can't get there this second but I wouldn't take any longer than necessary in case you have something else going on..