Discovery 4 - Boost Solenoid Circuit Malfunction

[JemJames]

Hi All

My Disco recently went into limp mode. I am not close to a Land Rover workshop and our local mechanic identified the problem after several days of research, as a 'Turbo Boost Solenoid Circuit Malfunction'. It was recommended I take it to a 4x4 workshop that does Dyno Tuning etc. They have said with the Disco the turbo is central and difficult to access. Due to go West in 2 weeks with 4 kids, and so I am hoping it wasn't an indication of a Turbo issue. Any thoughts of whether I should be concerned would be greatly appreciated.

Thanks, Jem

[DieselLSE]

Hi All

My Disco recently went into limp mode. I am not close to a Land Rover workshop and our local mechanic identified the problem after several days of research, as a 'Turbo Boost Solenoid Circuit Malfunction'. It was recommended I take it to a 4x4 workshop that does Dyno Tuning etc. They have said with the Disco the turbo is central and difficult to access. Due to go West in 2 weeks with 4 kids, and so I am hoping it wasn't an indication of a Turbo issue. Any thoughts of whether I should be concerned would be greatly appreciated.

Thanks, Jem
Be concerned. It may be something relatively simple to fix, but taking your chances could ruin your trip. Take it to an Indy, not a general mechanic or turbo shop. Others on here can advise who. Failing that, get it to a dealer.

[Eric SDV6SE]

+1 on that. Assuming you have the single turbo 2.7, you have one solenoid that controls the turbo operation. The 3.0 TD or SD have sequential turbo chargers and therefore two solenoids. These do fail, or the vacuum lines to them fail. Easy to diagnose with a vacuum test kit by a reputable LR independent. The solenoid itself is not expensive and easy to replace.
Part number is LR021929
Genuine Land Rover Kit - Actuating Lever - LR021929 | Rimmer Bros (https://rimmerbros.com/Item--i-LR021929)

Get it checked over by a lr mechanic would be a good first step.

[DazzaTD5]

Some fault codes from your mechanic would be clever, as would if its a 2.7 or a 3.0 or or or? but saying that...

*Someone, you, your mechanic (whats his/her problem, a D4 isnt a space ship) needs to look over hoses, vac lines etc etc for something thats split or popped off
*if a 3.0lt the Turbo Boost Solenoids are on the front righthand side of the engine as Eric has pictured one of them, look over all the 6 rubber lines that go to and from them and look for any that are split or come off. Follow all these rubber lines down across the front to the left side and again look for pipes that have come off. What is quite common is these rubber lines get oil on them and swell up and fall off. Right under the main top coolant hose is the prime area where oily residue gets onto the rubber hoses and kills them

[SeanC]

If it’s the 2.7 I had a similar issue. Engine system fault and lack of power.

The logged fault was:
P132B-22 Turbo/Supercharger Boost Control A
General Signal Failure - Signal Amplitude >Maximum

Turned out the solenoid was fine but the actuator was stuck.
Freed and lubricated just over 2 years ago and still good.

This is a video showing where the actuator is and how to check if it is working.

How to Check Your Turbo Actuator - TDV6 Range Rover Sport - YouTube (https://www.youtube.com/watch?v=jcKpRylro50)

If not moving or not moving the full range, make a wire tool similar to the one below. Slip over the ball on top of actuator arm and move back and forth spraying with lubricant. You should feel it freeing up. With any luck, problem solved.

173431

[JemJames]

[QUOTE=SeanC;3107949]If it’s the 2.7 I had a similar issue. Engine system fault and lack of power.

The logged fault was:
P132B-22 Turbo/Supercharger Boost Control A
General Signal Failure - Signal Amplitude >Maximum

Turned out the solenoid was fine but the actuator was stuck.
Freed and lubricated just over 2 years ago and still good.

This is a video showing where the actuator is and how to check if it is working.

How to Check Your Turbo Actuator - TDV6 Range Rover Sport - YouTube (https://www.youtube.com/watch?v=jcKpRylro50)

If not moving or not moving the full range, make a wire tool similar to the one below. Slip over the ball on top of actuator arm and move back and forth spraying with lubricant. You should feel it freeing up. With any luck, problem solved.

173431Thanks so much. That is very helpful. Appreciate you taking the time to post.

[JemJames]

Hi All

I can report the road trip went well, until we got home. We did a small amount of beach driving and drove through a couple of small creek crossings (maybe 20cms high and 20m long). Got home and stayed put for a few days. Next time I drove the Disco the park brake would not release (I was parked up a steep driveway). I waited an hour and it released and I managed to get home. The Independent Land Rover workshop in our area has quoted $1,600 for a new electric Park Brake plus labour. Having a look on-line this seems to be a not uncommon occurrence. I would appreciate any feedback on the best course of action to take. I have not researched whether a non genuine part is an option. I am reluctant to do this, I we used non genuine for the brake pads and they squeak....

Thanks in advance, Jem