Mystery freelander TD4 idle issue

It is possible you have 2 separate issues and one is being masked by the MAF sensor.
Firstly the MAF must be a genuine Bosch or you'll have no end of problems.
Second, have you fitted the new low pressure pump and filter yet. If not, fit them first and eliminate that possibility.
Then we can move on from there.
Mike

genuine bosch...not just the sensor but sensor with housing.

I don't know what HPFR sensor wiring is

Skinny Mike said:

It is possible you have 2 separate issues and one is being masked by the MAF sensor.
Firstly the MAF must be a genuine Bosch or you'll have no end of problems.
Second, have you fitted the new low pressure pump and filter yet. If not, fit them first and eliminate that possibility.
Then we can move on from there.
Mike

Click to expand...

Yeap genuine bosch fitted.

yeap hopefully tomorrow ill have them fitted.

Thanks

Jeremy

V8 Addict said:

Yeap genuine bosch fitted.

yeap hopefully tomorrow ill have them fitted.

Thanks

Jeremy

Click to expand...

Hi Jeremy
Does it rev and idle ok with new MAF disconnected ?
If so, I would suspect an intake air leak between MAF and inlet manifold (more specifically MAF and turbo inlet as first suspect) causing a low MAF reading as Metered Mass is bypassed.
I don't suspect a fuel pressure issue at all if the vehicle will idle and rev with maf disconnected.
Joe

HPFR = High Pressure Fuel Rail, also known as the injector loom wiring upgrade. The wiring can degrade on the injector loom and cause issues. Have a look to see if there's anything obvious.
It is possible there is an issue with this. But one thing at a time. Pump and filter first, then we'll go from there. No point spending more money unless you have to.
One of us will drop on the answer.
Mike

Joe_H said:

Hi Jeremy
Does it rev and idle ok with new MAF disconnected ?
If so, I would suspect an intake air leak between MAF and inlet manifold (more specifically MAF and turbo inlet as first suspect) causing a low MAF reading as Metered Mass is bypassed.
I don't suspect a fuel pressure issue at all if the vehicle will idle and rev with maf disconnected.
Joe

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yes it does idle and rev ok with new maf disconnected.

do you have to lift the car to see the turbo? where is it hidden?

I'm still changing the low pressure pump since these things go apparently....and I want to avoid any future down time in the future.

Skinny Mike said:

HPFR = High Pressure Fuel Rail, also known as the injector loom wiring upgrade. The wiring can degrade on the injector loom and cause issues. Have a look to see if there's anything obvious.
It is possible there is an issue with this. But one thing at a time. Pump and filter first, then we'll go from there. No point spending more money unless you have to.
One of us will drop on the answer.
Mike

Click to expand...

ahhh...this I did check, by unclipping the sensor, the car both with maf connected and not connected, in both cases with the sensor unplugged the car did start to work rough and badly on idle, so I imagine its oki.

Do you have access to a diagnostic tool that will display live data? You really want to see what the sensors are doing, so you can pinpoint the problem. It's possible that you have multiple faults, one masking the next.

V8 Addict said:

yes it does idle and rev ok with new maf disconnected.

do you have to lift the car to see the turbo? where is it hidden?

I'm still changing the low pressure pump since these things go apparently....and I want to avoid any future down time in the future.

Click to expand...

I think you will find it is simply an air leak if it is fine with MAF disconnected (standard ECU MAF map fallback mode) with the MAF connected it will rely on the MASS flow info from the MAF, any induction leak will cause just your issue.
I do not own a TD4, mine is an L series so regarding info on the turbo location and access Mike or Nodge can tell you.
Check the pipe clips and hose from maf to turbo inlet to start with - even if it means removing hose to visually check it.
Joe

Turbo, as you look at the engine from the front, it's bottom left rear. Access by removing the bottom skid pan.
Don't get to carried away. Do one thing at a time.
Mike

The engine will still rev ok with a failed turbo, so it's unlikely to be that. Joe is quite correct, that an air leak can cause issues. Live data can still be used for checking both low and high rail fuel pressure, air mass going into the engine and so on

Nodge68 said:

The engine will still rev ok with a failed turbo, so it's unlikely to be that. Joe is quite correct, that an air leak can cause issues.

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Agreed Nodge mate, also, the maf disconnect = ok (and new maf fitted) is a virtually textbook classic diagnosis of post MAF unwanted air intake. Fuel smell at rear was possibly simply un-burnt fuel.

Dear all,

I fitted the new pump and that didn't sort it out.

So then once the car was on a ramp, I started looking at the pipes from the maf to the turbo. And the turbo pipe was disconnected, so I put it back in place,

and the car now is very happy and I am even more happy

thank you all very very very much for your help!

V8 Addict said:

Dear all,

I fitted the new pump and that didn't sort it out.

So then once the car was on a ramp, I started looking at the pipes from the maf to the turbo. And the turbo pipe was disconnected, so I put it back in place,

and the car now is very happy and I am even more happy

thank you all very very very much for your help!

Click to expand...

great it's all sorted and is always a relief as u keep banging ur head against the wall in trying to find what's wrong

is good u replaced the pump and filter as it will be one less thing to worry about

V8 Addict said:

Dear all,

I fitted the new pump and that didn't sort it out.

So then once the car was on a ramp, I started looking at the pipes from the maf to the turbo. And the turbo pipe was disconnected, so I put it back in place,

and the car now is very happy and I am even more happy

thank you all very very very much for your help!

Click to expand...

No worries, click a huge like to my diagnosis and solution and remember occams razor ....
You owe me several dozen pints - !!! - never go searching for the expensive stuff ! - consider the actual logical issue.


Cheques by post please...
Joe

(Never a word of thanks..................)

Joe_H said:

No worries, click a huge like to my diagnosis and solution and remember occams razor ....
You owe me several dozen pints - !!! - never go searching for the expensive stuff ! - consider the actual logical issue.


Cheques by post please...
Joe

(Never a word of thanks..................)

Click to expand...

ur rewards will be a big cake

gstuart said:

ur rewards will be a big cake

Click to expand...

Oooooooooooooooooooooooooooooooooooooo

That Blue Beasty thing will be all over me like a bloody rash if you mention the C word...................

gstuart said:

great it's all sorted and is always a relief as u keep banging ur head against the wall in trying to find what's wrong

is good u replaced the pump and filter as it will be one less thing to worry about

Click to expand...

nah I'm not worried for the pump less down time in the future

Joe_H said:

Oooooooooooooooooooooooooooooooooooooo

That Blue Beasty thing will be all over me like a bloody rash if you mention the C word...................

Click to expand...

was trying to think myself regarding the hose , if it was the vacuum hose that went to the turbo actuator or the turbo hose at the front, the one that rubs against the screw , if that makes sense , as when that one comes off it normally creates a lot of black smoke

V8 Addict said:

nah I'm not worried for the pump less down time in the future

Click to expand...

will be a saviour seeing we are going towards the winter months

been there done that and is horrible changing that in the cold and it's raining