Freelander 1 TD4 Misfire & Loss of Power - Solved

Thought this might be worth a new thread, mentioned on others previously but may help others.
2004 TD4 reports of loss of power on hills and misfire.
LP pump making noise like demented Swan, so suspected that.
Measured live pressures and revealed:
Across range 1000 to 3000 rpm.
Airflow 455 to 365
Manifold pressure 100 to 115
Lp pump 375 to 325 kPa
Hp pump 28600 to 59400 kPa

So all looks good.
Won't fail while I am driving it, but after a run uneven tick over is present and hp pressure is peaking upwards while ticking over, up to 33500 kPa. Just for a short burst.

I have cleared numerous fuel pressure codes which have not returned: P0191, P1195, P1260, P1470
Suggesting all is unwell, or has been unwell, with the fuel pressure.

Suspect fuel rail sensor or connector, but want it to fail before fixing it!!

Road testing today. Will report back. May be a pressure loom or connector issue.
Any other ideas please??

The LP is a little low, but should still perform ok. The MAF signal is way off though. This will limit power, as the EDC is trying to keep the anti smoke map happy. This would explain the low rail pressure you're getting. Try unplugging the MAF and giving it another test.

Thanks. Car eventually failed to start and fortunately I was monitoring faults. P0191 rail pressure offset. Whilst it was in failed condition I removed the plug to the fuel rail pressure sensor and contacts all green!! Electrical contact cleaner and fit / remove several times and car started and idle is now even.

Unplugged MAF and airflow went up so removed MAF and cleaned with contact cleaner. I know this is controversial but hey, it worked. Range is now 330 to 680.

So that is all good news. Opened rear door and window dropped and jammed!!!

Cable snapped. Why did it do this when I touched it!!??

New regulator on order with all filters to finish the job.

Clean MAF produces an increase of 10000 kPa at 3,000 rpm on the hp fuel rail.

Thanks for advice. Low cost repair, except for rear window!!

Had a similar problem would not start after a hot run bad misfire at a specific rpm code as seen in pictures
But my has had the wiring overlay upgrade ( not by me ) took the plug out cleaned wd40 back on and it all seems well

Dar ran Dar ran said:

Had a similar problem would not start after a hot run bad misfire at a specific rpm code as seen in pictures
But my has had the wiring overlay upgrade ( not by me ) took the plug out cleaned wd40 back on and it all seems well

Click to expand...

All as been well 400 m stop starting and ticking over for long periods not missed a beat
I would recommend checking this even with the upgrade , this Freelander had not moved for 4m before I bought it
Not sure if that caused the problem