Loss of power 2.5 T5 BNP

[Blakes87]

Hi All.


Newbie here with a 06 T5 2.5 LWB. I have pretty much had every failure possible with this from ABS pump to engine re build but while it keeps putting a smile on my face I'll keep repairing 😏.


Luckily for me the reason why I'm posting here today is not because of a problem with my van but an ongoing issue with my father in laws 2009 T5 2.5 (BNP engine) with a loss of power that I'm hoping someone can help with.


I'll start from the beginning with this so anyone willing/able to help has the full picture.


The T5 was purchased a few years ago and after a few weeks was re mapped. Nothing to report other than basic servicing and brakes until a few weeks ago suddenly a loss of power, EML on and black smoke. Some quick diagnostics found a turbo under boost code and a split N/S intercooler hose. All was put right and road tested.......... only to find still a lack of power, EML returning but no black smoke (turbo under boost fault returned). Adding to the problems the emission light now flashing with the DPF blocked (possibly caused by the over fuelling and black smoke from the air leak). The van was sent away to have the DPF and EGR removed and mapped out from the PCM plus a slight adjustment to the map that was originally carried out a few years ago. It was then driven around 30 miles back home with a clear lack of power still as the turbo under boost issue had not been resolved however strangely enough no lights came on or faults stored in the PCM. So I then went about going over everything I could think of to try and resolve this issue checking the air filter, hoses, vac pipes, intercooler, turbo with the only issue to not was excessive play in the turbo bearings. Knowing this wouldn't last much longer anyway this was changed with a new unit and to no surprise the last of power still remains. Although no faults return to the PCM I still feel this is a turbo under boost issue).


Yesterday I re interrogated the air pressures using auto logic and found the following


@idle
MAF 580mg/h
Actual charge air pressure 1193mbar (seems about right at idle given atmospheric pressure is 1000mbar)


@3700 rpm with foot to the floor in 4th
MAF 605mg/h (doesn't seem to have increased much from idle??)
Desired charge pressure 1642 mbar
Actual charge pressure 1213 mbar (only approx 6 psi different from desired so wouldn't say much difference to what the PCM is asking for)


Sorry for the long post but I wanted to include everything to try and get to the bottom of this. I fix Landrovers for a living but this one is leaving me stumped!!!!


Hopefully someone has hand this issue or can give some pointers on what else to check.


Thanks in advance!!


👍🏻

[Rob69]

can you try swapping the MAF sensor from your van to his and give it a try?