P0089 Fuel Pressure Regulator 1 Performance

Discussion in 'LR4' started by BMullensNH, Jun 10, 2019.

  1. mklinker

    mklinker Full Access Member

    Age:
    27
    Posts:
    75
    Likes Received:
    21
    Joined:
    Aug 3, 2018
    Location:
    boston, ma
    There is no way to check the high pressure fuel rail pressure... there is no valve to test from and it is in the thousands of PSI's.
     
  2. BMullensNH

    BMullensNH Member

    Age:
    54
    Posts:
    10
    Likes Received:
    1
    Joined:
    May 11, 2019
    Location:
    Boston
    UPDATE: The light went off after driving it for a few days, and hasn't returned. Leaving for a 15 hour drive tomorrow. We'll see what happens........
     
  3. howardduff

    howardduff Full Access Member

    Posts:
    62
    Likes Received:
    6
    Joined:
    Jan 2, 2014
    Location:
    Cleveland, Ohio
    I have had the fault for several weeks now. I retired from a Ford engine plant just after Ford sold JLR. I checked with an engine engineer I knew and he gave me some pointers from when he had to do the trouble shooting problems with high and low pressure fuel pumps on Jag engines. He said the P0089 code is usually due to an issue with the HP fuel pump and the fuel pressure regulator is an integral part of the pump. Bosh and Denso were the suppliers with Denso pumps having a weak spring problem. This was eventually corrected. If it is a low pressure pump problem it is usually due to debris in the fuel lines and found early on under warranty. It will also pull other codes with the P0089 code. He also said that many times the pressure sensors were the problem and that should be the first part to replace since they are the least expensive. Looking at the video in the P0087 post it looks like the high pressure pumps are on the right side of the engine possible behind the inner fender liner. I still don't know where the pressure sensors are located. As I find out more I will update this post.
     
    stl8grey likes this.
  4. stl8grey

    stl8grey Full Access Member

    Age:
    42
    Posts:
    55
    Likes Received:
    15
    Joined:
    Feb 4, 2016
    Rail sensor, LR012280, is located on passenger side at the firewall just behind the cylinder head. A crows foot size 1&1/16 fits the sensor just right. Run a few extension on a ratchet from the front of engine towards the back in between valve cover and battery. 20190627_134024.jpg

    Low pressure sensor LR015356 is on passenger side of transmission behind a tin shield. Looks just like it does in the video. That one is not as fun to r&r. I opted to just unscrew sensor from the fitting versus depressing the quick disconnect on the line. 20190627_135019.jpg

    This was on an LR4 with the 5.0.
     
  5. BMullensNH

    BMullensNH Member

    Age:
    54
    Posts:
    10
    Likes Received:
    1
    Joined:
    May 11, 2019
    Location:
    Boston
    Thank you very much for the info! 3 miles into our 15 hour drive and the check engine light kicked on. Unreal! Drove the entire time, no problem. No loss of power, gas mileage averaged approx 21 mpg at 70+ mph. Will look into fixing this myself when I get back home.
     
  6. howardduff

    howardduff Full Access Member

    Posts:
    62
    Likes Received:
    6
    Joined:
    Jan 2, 2014
    Location:
    Cleveland, Ohio
    I have finally had my 2015 LR4 repaired for the exact same code you show on your first post. I have a generic code reader and it showed the P0089 code with know explanation. I took the vehicle to an auto parts store and it showed exactly what you had on your first post High Pressure regulator bank 1. After looking under the hood and from under the vehicle I couldn't find access to the high pressure sensor I decided to take it to my local independent rover repairman. He scanned it with a typical dealer program and found the code P0089-64 Fuel Pressure Regulator 1 Performance - Signal plausibility failure. It showed it as 100%. He installed a new High Pressure fuel sensor and it didn't clear the fault. He ended up installing the low pressure fuel sensor also and that cleared the fault. His next step would have been to install a new fuel pump.
    I asked to see how they found the High Pressure sensor and found they removed the main battery and battery holder. The fuel rail and sensor are very accessible at this point. This would also give you good access to the no. 3 spark plug. I understand the low pressure sensor is under a heat shield on the right side of the transmission.
    This has been the second time I have had to have this repaired, once under warranty. If it happens again I will attempt to repair it on my own knowing how to gain access.
    Please keep us posted on what you find on your vehicle.
     
  7. Storr32

    Storr32 New Member

    Age:
    45
    Posts:
    1
    Likes Received:
    0
    Joined:
    Jul 26, 2019
    Location:
    South Carolina
    This specific code is set by the low pressure pump in the tank. JLR has released a PCM update to address this.
     
  8. BMullensNH

    BMullensNH Member

    Age:
    54
    Posts:
    10
    Likes Received:
    1
    Joined:
    May 11, 2019
    Location:
    Boston
    UPDATE: I took the vehicle to a local Indi repair shop and they used a more advanced code reader and found the issue to be tied to the "Oxygen Sensor-Downstream Right". Total cost to replace the sensor and clear the codes was $295.86. No apparent problem with the fuel pressure sensor.

    The Tech, who was with the local LR dealer for ~8 years said that the P089 code was driven somehow by the oxygen sensor code being tripped. He described it (or maybe better said that I understood it), as the codes can cascade from one to another and the less sophisticated readers aren't able to capture the true cause of the check engine light coming on.

    Regardless, the lights are off, the truck runs great and all is good. I'll report back if anything new pops up.
     
  9. stl8grey

    stl8grey Full Access Member

    Age:
    42
    Posts:
    55
    Likes Received:
    15
    Joined:
    Feb 4, 2016
    Awesome. He is correct in his "cascade" description.
     
    BMullensNH likes this.

Share This Page