Freelander 2 loss of boost

I have a strange 1 and its driving me insane
Freelander 2 07
Car generally runs fine but when warmed up every now and then I get a loss of boost. I have an obd plug and torque app and can see it boost up to 22.5psi most of the time but sometimes it just all of a sudden drops. If I let off the pedal and back on it will boost fine. Revs always remain unchanged. No codes and no eml

Ive changed:
Throttle body
Manifold presuure sensor
Air temp sensor
Fuel filter
Accelorator pedal
Had turbo actuator tested no faults
Made sure actuator arm and veins move freely and lubed.
Problem still exists

Im thinking could be:
In tank fuel pump
Fuel rail pressure sensor
Stop light switch (apparently the ecm monitors this)

If I unplug the maf will the car still run using a pre-set values?

My old mk1 freelander would.

Any ideas?

Cheers

It won’t be the in tank pump as there isn’t one that supplies the engine with fuel - the high pressure pump has a low pressure mechanical pump on the back of it which draws fuel from the tank.

Have you monitored fuel rail pressure to see what it’s doing?

What does the pump in the tank do?
Fuel pressure dips and raises at the same point but that could be due to less demand.

Pump in the tank transfers fuel from one side of the tank to the other as it’s a saddle tank so it keeps the fuel level consistent across both sides

What is the egr valve doing when the issue occurs?

The egr readings are always up and down.
If I use a plate to blank it off theres no difference.
Could the egr itself give off an incorrect signal or affect boost if it sticks open?
It only happens after 20mins or so once engine is real warm. I suspect an ele trical item breaking down with heat

I soaked maf in brake cleaner and flushed out the intercooler which produced alot of crap.
Problem still exists
Will try new maf and egr next
Cheers

Yes if the egr sticks open you will loose power. I would try the maf first and blank off the egr next, I wouldnt fit a new egr.

Ok so I blanked off egr no change.
I cleaned maf no change
I unplugged maf and fault goes away but I have noticed that without the maf plugged in it stops the egr from working too so I suspect it’s still either the maf or egr or maf wiring.
I will look at getting egr mapped out to elimate that and then try a new maf.

After a lucky chat with a mate I have tried a known working maf and the issue returns with that installed and plugged in.
Suspect sticking egr now.
Will see about getting it mapped out.
I hope that solves it otherwise it’s loom failure.

Egr mapped out and all is well. Boosts much better and more responsive.

round said:

Egr mapped out and all is well. Boosts much better and more responsive.

Click to expand...

May I ask what was the price for the remap?

£140