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i have in the shop a 2018 ford transit 350 with a 3.5l ecoboost with code p0299. cleared the code, drove and came right back, seems a bit weak to me but first time driving one of these. visual inspection showed intercooler has been damaged on one corner and someone had tried to jb weld it. intercooler oil soaked in the same area so i thought a no brainer. replaced intercooler, cleared codes and drove. code comes back in less than a mile, power feels better first few hundred feet but feels weak by the time it hits second gear. using snap-on scanner(up to date) and alldata for diagnostics but scanner does not show some of the pids alldata says to check. only pids i really see for boost pressure is desired boost, boost at throttle body and map sensor. watching data koeo everything reads around 14psi. engine idling map drops to around 6 psi but everything else stays the same. while driving hard acceleration desired goes up to around 29psi for the first few seconds after clearing codes but then drops down to around 20 psi max. boost at throttle body usually stays around 14 psi, dropping under acceleration and spiking up a little when you drop the throttle. i have never seen the map sensor show above 14.5 psi.
i do not have a high pressure smoke machine but i rigged up just an air line regulated to around 15 psi and listened with a stethoscope hose. only leak i can find is between air box and turbo; not on the boosted side. set up is a little noisy so small chance i might not be hearing something over regulator letting air into system.
blow off valve seems fine when powered up. it is not the ones with the visible orange diaphragm that busts one the f150s. can not see inside of this one. tried sticking a hose over it and blowing into and could not. do not think it is by-passing. also tried to clamp off return hose from blow off valve to low pressure side and revving engine to see if it changed pids any on scanner and it did not.
do not mess with turbo cars much so this is a learning curve for me digging in this deep. biggest thing throwing me off is boost pressure at throttle body staying around the same no matter the engine load and throttle position. i tried another new sensor(standard brand box but sensor looked the same with some of the markings on top scrapped off, rebrand/box?). reading went from 14 psi to 37 psi engine off and started throwing engine problem warning message with engine running so i never drove.
also installed an aftermarket boost gauge(manual) and ran engine in the shop throttling up and it never showed any boost; even power braking.
waste gates are in closed position and move when adding air pressure to actuator.
anybody got an ace up their sleeve that can point me in the right direction? is the boost at throttle body reading correct?
