The Mitsubishi Pajero Owners Club®

[iam_TJ]

Various threads and comments here talk about the 6G74 engine and P0190 fault codes caused by micro-filters in the High Pressure Fuel Pump (HPFP) located on the rear of the engine block.

However, I cannot find any mention of a HPFP in the Mitsubushi, Haynes, or Russek manuals.

All I can find is mention of the high pressure line from the in-tank pump leading to the Fuel Pressure Regulator (FPR) that feeds the two banks of injectors.

Is the FPR actually what is being referred to when folks talk about the HPFP and micro-filters ?

[Google]

[iam_TJ]

Answering my own question! Yes, there is a high pressure fuel pump. It is on the rear of the engine next to the bulkhead. It is fed by three fuel lines. It is before the fuel pressure regulator which is directly attached to the fuel rails feeding the injectors.

Manuals make passing reference to it but do not show it in any photographs, sketches, or schematics. I eventually found it referenced in the workshop manual at 13A-239 although it makes no mention of the micro filters.

[administrator]

[ShogunItHurts]

Hi TJ

You seem to be working through a lot of the same issues I'm currently chasing. So far I have replaced the tank and the filler neck but I'm still getting error codes popping up if I try to give it max throttle at high revs. I've replaced the microfilter at the high pressure pump since replacing the tank but I'm now considering more drastic action to try and fix this once and for all. I want to fit an inline filter in the high pressure feed line which will be easier to service, this is happening so often it's getting frustrating. What I'm trying to work out is just how fine does the filtration need to be to make the microfilters redundant? On ebay there is a seller called Torques_U.K. who supplies inline filters down to 10 micron and even an ethanol specific version down to 6 micron but I have no idea what the standard microfilter is specc'ed at. It would be nice to know I have the right level of protection to remove the microfilters completely and be done with them!

On top of this I'm also wondering if the in tank pump is suffering from old age and not helping my cause, again from searching ebay it looks like a Walbro GSS342 would be more than capable of supplying fuel at the required pressure and flowrate, it might even take some strain off the high pressure pump on the back on the engine.

I'd be keen to hear any ideas and solutions others have found, I know I want to keep this truck as it does everything I need and actually has very little rust so is definitely worth keeping. I'm hoping this forum isn't completely dead yet...

cheers
Mark