Hey everyone, Got a question for you all... Ive got a 2022 Volvo FE DUAL CONTROL here that is used as a garbage truck in australia. Originally came in for a blown head gasket, truck was coming to a midlife rebuild so the customer decided to replace the head along with the head gasket at the same time. After these were replaced, the truck had a low pulling power fault, the variable geometry turbo was replaced as the truck was underboosting at the time. Even after the turbo replacement, the truck was gutless and had no pulling power, myself and a few other technicians have had a go at this truck. so far, we found that the intake manifold pressure sensor was reading erratically, found that the sensor node was covered in oil, have replaced the sensor and double checked the values from the engine harness/ecu side and was found to be all good, recalibrated the sensor after replacement. The variable geometry turbo was unplugged and also found to have good values on the engine harness/ecu side. Performed tests for the turbo to check the actuator position and see if it was actuating fully, found to be all good. performed an intake pressure test to check for air leaks in the system, found no leaks and was all good there. Truck still has low pulling power fault. went for a road test with live data being read out and found that the exhaust pressure seemed high, so the truck was temporarily straight piped and truck was still sluggish, also replaced the dpf filter and the backpressure sensor as 2 burns were completed to still have high backpressure at idle. Checked the exhaust pressure governor for a full range of movement, found to be all good there, could not be faulted. checked the movement of the EGR valve and verified it was opening and closing as intended. checked the fuel/water separator for water and ensured it didnt have any in the fuel system, another technician diagnosed that the low fuel pressure sensor was faulting and had replaced that. performed a fuel compensation test, all was good there and had minimal compensation across all cylinders. Checked the readable soot level and found that it was reading 14%. performed a Common rail fuel pressure test and it was reading 110,000kpa at approximately 1,500 - 1,700 rpm. checked the air filters and found they were still brand new. Vehicle has an automatic Allison transmission, does not feel like the torque converter is slipping. Motor is boosting fine inside and outside of workshop, reading boost pressure 253kpa on a road test, and reading 181,000kpa on a road test. Fuel filters were replaced to be sure that they werent clogged and causing issues. Have checked the the intake valves to check for clogged soot, no issues there. I'm at a complete loss for what else i can check, my next idea is to perform a check on the valve clearances and also perform a compression test. Apart from this, im at a complete loss for what to check next, if anyone has any ideas, it would be greatly appreciated as im losing my mind over this. Have that funny feeling that it is gearbox related, but currently have no way of verifying as my company outsources transmission work for Allison gearboxes. Thanks in advance
I don't know the particulars of the trucks but the core engine is the same across product lines. Which engine do you have, D13?
It's a D8k280, I wish it was a D13 lol
Well, I'm sorry. I have zero experience on that. Is it Volvo or Volvo/Penta ? I wish I could help.
Yeah it's a volvo
Update, I figured it out, performed the boost monitoring test again, found that it was reading erratically again, pulled the brand new sensor out to find it was covered in oil residue again, ended up checking the intercooler for oil pooled at the bottom and found that it was a quarter filled with contaminated oil, pulled the intercooler out and tipped it upside down to drain it (didn't have a drain plug) and had nearly no flow out of the intercooler whatsoever, so I'll end up replacing the intercooler whenever it arrives
Great catch.