Peugeot Expert 2015. P1471...and others.

[ImNoExpert]

Hi everyone. I've had so many issues since May last year that they may or may not all be related.

Low power/boost especially at higher speed/gears. No fault codes on the van itself but my Peugeot Citroen FAP app and Diagbox 7.76 report P1471......only after I tried to diagnose the problem by removing the electrovalves. 1618QQ Turbo/EGR and 1618HR Pressure Converter.

I've checked, double checked and quadruple checked and everything looks as it should be going back together.


Symptom now is the Air Doser is opening and closing at idle to the point of almost stalling and it won't rev. P1471 Open Circuit. The 1618HR valve is very hot, so wondering if it's shorted?


The van had a leaking injector when I got it, so bad that the entire top of the injectors and rail are covered in brown tar. I've assumed the valve breather atop the engine has sucked up hot diesel fumes etc into each valve and cooked them, destroying or impairing the vacuum and diaphragm. Upon inspection they did look a little blocked and I could not attain a vacuum on either of them. I picked up 2 N75 valves form the breakers from a Citroen...2.0hdi and put one one first the day before. We changed the middle one that operated the turbo; No codes, no change in performance. Both of these held a vacuum. Today I swapped the one that controls the Air Doser, but I also removed the 1618HR valve Pressure Converter at the same time (I think) It also looked blocked but not entirely. I used WD40 and 99% isopropyl..........Now wondering if the isop ruined the Pressure Converter?


I can't take any more. It was running just very slow in acceleration and farting on acceleration. No apparent leaks from exhaust. DPF pressures seem in tollerance at less than 10mbar at idle and around 30mbar at 200rpm. Max under load is around 300mbar or less. Is this normal pressure?


I hope someone can help me. It's now stuck on my drive. I've ordered a new 1618HR valve which might take 3 days to arrive. Completely broken with this van now.

[ImNoExpert]

Can anyone help me with a Wiring Diagram of the Vac sols on my engine please? Which plugs go where.

This engine has been out in the past, and need to confirm everything is in the right place. Thanks.


I've ordered a new 1618HR Pressure Converter Valve, but suspect all 3 sol's might need replacing.