Freelander td4 MAF

bfgquinn · Jul 31, 2017

Hi
I've been trying for a while to sort out what I thought was a MAF issue on my 2005 Freelander td4...really sluggish under 2000 revs but when the turbo kicks in it takes off, then when i change up the revs drop below 2000 and its sluggish again especially on gradients...changed 1 injector last year, two different MAFS Peerburg and Bosch still no change. Yesterday I installed a new cam sensor after a starting issue and cleaned the MAP sensor and intake sensor then thoroughly cleaned the intake manifold, i can hear both fuel pumps kick in and changed the fuel filter a few months ago....connected MAF...same issues.it's a little rough on start with some light smoke but this clears... I used an OB2 scanner, no faults (dealer seen the MAP and MAF faults and cleared) and it's reading the MAF, MAP and intake temp values. Been running with the MAP disconnected and it's acceptable but not it's best. Is this now an ECU problem. First time on here and I've read a few posts on MAF problems but I think I can now discount many of these.

Nodge68 · Jul 31, 2017

It won't be an ECU problem. It's more likely a vacuum pipe problem. It sounds like you have a delayed boost problem. The boost control solenoid on the TD4 requires a decent level of vacuum to work. If you have a damaged or leaking vac pipe in the system. Then boost will be delayed until the vac pump is working hard enough to overcome the leaks.

The TD4 is actually quite sluggish to get into boost, by comparison to other turbo diesel engines. Mine takes a good second to go from running off boost, to full boost.

bfgquinn · Jul 31, 2017

Nodge68 said:
It won't be an ECU problem. It's more likely a vacuum pipe problem. It sounds like you have a delayed boost problem. The boost control solenoid on the TD4 requires a decent level of vacuum to work. If you have a damaged or leaking vac pipe in the system. Then boost will be delayed until the vac pump is working hard enough to overcome the leaks.

The TD4 is actually quite sluggish to get into boost, by comparison to other turbo diesel engines. Mine takes a good second to go from running off boost, to full boost.

Thanks for the quick reply, is this the braided hose that goes to the EGR?

Nodge68 · Jul 31, 2017

bfgquinn said:
Thanks for the quick reply, is this the braided hose that goes to the EGR?

If you are talking about the vacuum pipes. Then yes, one goes to the EGR valve. There are others that are all linked together. One larger pipe goes to the brake booster. Another goes over the top of the cam cover and down to the turbo boost solenoid valve. This one often wears through where it rubs on various components.
Also make sure the turbo filter is replaced.

bfgquinn · Jul 31, 2017

I had a look and no obvious tears or wear on the vacuum pipes, any idea what the vacuum pressure should be and I could test with a vac gauge?...With the MAF disconnected there's no problem with boost though still getting a bit of light coloured smoke and some shuddering while warming up...I also seem to have a spare sensor plug front left of the engine bay not connected to anything?

Nodge68 · Jul 31, 2017

bfgquinn said:
I had a look and no obvious tears or wear on the vacuum pipes, any idea what the vacuum pressure should be and I could test with a vac gauge?...With the MAF disconnected there's no problem with boost though still getting a bit of light coloured smoke and some shuddering while warming up...I also seem to have a spare sensor plug front left of the engine bay not connected to anything?

Vacuum should pull about 31Hg on a vacuum gauge.

Where's the spare plug? Can you post a picture?

Skinny Mike · Jul 31, 2017

Check the vacuum reservoir is in good condition. Wouldn't be the first time one of those was leaking.
Mike

bfgquinn · Jul 31, 2017

Nodge68 said:
Vacuum should pull about 31Hg on a vacuum gauge.

Where's the spare plug? Can you post a picture?
Thanks again...the plug It's part of the loom front left and hanging loose on the belt side near the air intake at the radiator ,looks like 2 pin but not the intake temp or MAP , can't see anything it should plug into but the lead is about 8 inches long

bfgquinn · Aug 1, 2017

Nodge68 said:
Vacuum should pull about 31Hg on a vacuum gauge.

Where's the spare plug? Can you post a picture?

Picture attached...

Andy Warren · Aug 1, 2017

bfgquinn said:
Picture attached...

Hi are the wires going to that connector black and the other purple with black trace ? if so on mine it goes to what looks like a horn/part of the alarm ? as you look down its just to the left of the intercooler pipe.

Nodge68 · Aug 1, 2017

What colour are the conductors?
Are they brown/ yellow and grey/ green.
If so, they are for the fuel burning heater temperature control switch.

bfgquinn · Aug 2, 2017

Nodge68 said:
What colour are the conductors?
Are they brown/ yellow and grey/ green.
If so, they are for the fuel burning heater temperature control switch.

Looks like brown/ yellow and white/green two pin can't see the switch you refer to though?

Nodge68 · Aug 2, 2017

bfgquinn said:
Looks like brown/ yellow and white/green two pin can't see the switch you refer to though?

That's part of the wiring for the Fuel Burning Heater. You won't have the switch if the FBH isn't fitted. If it is fitted, you'll see the heater's flue/ exhaust under the LH front bumper corner.

bfgquinn · Aug 2, 2017

Nodge68 said:
That's part of the wiring for the Fuel Burning Heater. You won't have the switch if the FBH isn't fitted. If it is fitted, you'll see the heater's flue/ exhaust under the LH front bumper corner.

Ah...thanks again buddy...I don't have it then and this is just a spare I would say...still the problem at hand is the turbo and now I'm thinking it's either the turbo itself or the solenoid for the variable nozzle turbo...the 2000 rev thing got me thinking that if the vanes were open at low speed and not closed like they should be then that would account for the lack of boost...If the solenoid is controlled be the ECU is the 2000 revs important? or alernatively it could simply be the vanes are stuck open...Does that make sense? I was just told I'd need another diagnostic that would be the third at £90 a go to find this out and I'm wondering why the first 2 found the injector and the MAF and not this...not trusting the local landrover guy right now...

Nodge68 · Aug 2, 2017

bfgquinn said:
Ah...thanks again buddy...I don't have it then and this is just a spare I would say...still the problem at hand is the turbo and now I'm thinking it's either the turbo itself or the solenoid for the variable nozzle turbo...the 2000 rev thing got me thinking that if the vanes were open at low speed and not closed like they should be then that would account for the lack of boost...If the solenoid is controlled be the ECU is the 2000 revs important? or alernatively it could simply be the vanes are stuck open...Does that make sense? I was just told I'd need another diagnostic that would be the third at £90 a go to find this out and I'm wondering why the first 2 found the injector and the MAF and not this...not trusting the local landrover guy right now...

The plug can be considered unused

Check all the vacuum pipes and vacuum receiver for leaks.

bfgquinn · Aug 4, 2017

Nodge68 said:
The plug can be considered unused

Check all the vacuum pipes and vacuum receiver for leaks.

well when the rain stopped I disconnected the lines from the reciever and got a vacuum then disconnected at the EGR and felt a vacuum there. I then disconnected and checked at the solenoid and at the filter and there's vacuum there...no leaks but I don't have a vac gauge to check vac pressure..will take a week to get one...did notice a marked increase in smoke when running while disconnected at the vac pipe to the EGR...any idea how I check the function of the solenoid and actuator?

bfgquinn · Aug 6, 2017

Well after disconnecting the hose to the solenoid and connecting to the actuator directly I went for a run...the performance was much the same as when running with the MAF connected but mate a smoother action from the turbo after 2000rpm but still less power at low speed.checked the actuator for movement at the linkage and filmed it up to 4000 rpm and as you can see from the movie there's movement but is it enough?

Skinny Mike · Aug 9, 2017

What movie?
Do I need popcorn?
Mike

bfgquinn · Aug 9, 2017

bfgquinn said:
Well after disconnecting the hose to the solenoid and connecting to the actuator directly I went for a run...the performance was much the same as when running with the MAF connected but mate a smoother action from the turbo after 2000rpm but still less power at low speed.checked the actuator for movement at the linkage and filmed it up to 4000 rpm and as you can see from the movie there's movement but is it enough?

So it's official...its the turbo probably full of crud ...

bfgquinn · Oct 31, 2017

Skinny Mike said:
What movie?
Do I need popcorn?
Mike

seems my wee movie didnt upload, been a bit of a saga but replaced 2 injectors with a couple of refurbs and the start and idle seem fine but still the same when trying to run and drops into limp mode wih the MAF connected, if i had a list of things that cause this limp mode i could at least tick them off...today ill be digging into the turbo.

Freelander td4 MAF

Member

Well-Known Member

Member

Well-Known Member

Member

Attachments

Well-Known Member

Well-Known Member

Member

Member

Attachments

Well-Known Member

Well-Known Member

Member

Well-Known Member

Member

Well-Known Member

Member

Member

Well-Known Member

Member

Member

Similar threads