Freelander 1 My TD4 SE Auto Misfire Thread

[Nodge68]

I've literally just put mine back on (day off looking after the dog) after I sorted the electrical gremlin.
Ticking over nicely, going for a run in a bit.
I read about the turbo boost thingy, sounds interesting. You'll have to let us know how it goes. I was reading @hd3 has put one on, think I'll do the inlet mod at some point, got to be better than the plastic job!
Mike

The inlet mod does look nice and should improve response I would think. What MAF are you using Mike?
I think I'm going to sort out the exhaust system next. The cat and rear box are incredibly restrictive to flow. This will really hamper turbo spool up. So next plan is to replace the rear box with a smaller straight through unit. Then I'll look at the cat to ascertain if it's blocked. I'll base what I do next, on the condition of the matrix.
I plan to attack the intercooler with the pressure washer as the core is full of crap. I'll clean out the interior of it at the same time with a good dose of petrol.
So far the TD4 is going well, with increased throttle response. It's not as lively as a V6 but it's not bad for a diesel. It's considerably better on fuel than the V6.

 

[Skinny Mike]

I've still got a bosch maf on. It was replaced under warranty about 2005, by landrover and has been fine since! Although I think it will go at some point.
Unbelievably, I've still got the original exhaust on, the power of waxoyle! The outer skin on the center box is pealing off, but as it's still working I see no point in changing it yet. Other jobs to do that have priority, but when I do change it, there's a place round here that build custom stainless exhausts, so I'll have one built to my spec.
I was cleaning out the cellar the other day and came across a brand new rad, that I'd bought back in 2009, totally forgot about it. The rad that's in was leaking so I got the replacement, then it stopped for no apparent reason? As it's a big job I thought I'd leave it til it started leaking again, 7 years on and it's still fine. But when it comes off the intercooler will be cleaned or replaced as well.
Mike

 

[Nodge68]

maf signal i would think ..

if you've not already tried it .. remove that outer sleeve from the air filter ..

( maybe not if regularly ' off-road ' .. or other scene where some
( forceful object might get sucked in ..
( i never see anything larger than an insect or two .. and the odd small leaf
( and .. you'd know more than me with regard to that
( just added for the benefit of any the not-so-mechanical minded readers

anyhow .. to cut a long story short ..
i did .. and the effect / response .. below 1500 rpm .. ( and above ) be just short of 'amazing' ..
well 'amazing' with a ron-box 2a+ / dash switch / and egr bypassed
sort of .. be like adding another number higher to the ron-box selections ..

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

You mean cut the fluffy covering off the filter? I have read about people removing it but can't see the reason for doing so. The TD4 is a small capacity turbo diesel with a massive air filter for its size. I can't see why a bit of fluffy nylon would make much, if any difference. I will try it however. I might just be surprised.

I removed the fluff from the filter this weekend. I also tested it's air flow ability, very crudely. Basically I passed air from my workshop vacuum through a piece of the fluff while monitoring the pressure in the vacuum pipe. I was amazed at just how restrictive the fluff is. So well worth removing IMHO.

 

[Skinny Mike]

I've got a piper cross open sponge filter. Been using it for years with no trouble. Just wash it every now and then.
Mike

 

[hd3]

@mike .. et al .. re :

I read about the turbo boost thingy, sounds interesting.

it feels to add some extra boost to a part of the rpm range preselected via some mini-switches
( a torque graph might show a bulge coinciding with chosen rpm range )
there's positions .. L / M / M-H / H .. to choose from

with the td4's vnt type turbo .. i imagine the device alters the behaviour of the turbo vanes
one by-product of its' operation .. seems to be .. adding a bit of engine braking ..
i.e. when right foot is let slightly off the go-pedal .. mid cruise ..
but not when foot is 'completely-off-the-pedal' .. as that i assume makes the vanes' angle as 'no-boost'

~~~~~~

i tried all the settings over a few days driving ..

H .. seemed a bit useless for the td4 .. it starts at 2800 rpm aprox.
M-H .. was interesting .. but engine coughed once at passing 2800 rpm under full go-pedal ..
.. and as i didn't want H in the equation .. decided to go with ..
M .. where i spend most of the time in regards to engine rpm ..
.. only issue with M is that the power delivery is 'peaky' ..
.. a bit undesirable ( for me ) when using lower gears in slow traffic ..
.. but .. out on the open ( ha ha ) road .. it's brilliant !!
L .. didn't seem to do much .. consigned it to the 'maybe-good-for-off-road' catagory

i was hoping the L setting would enchance engine response time to go-pedal movement .. When ..
using the lower power setting on the ron-box 2a .. but L setting didn't seem to help ..
so motored on using the M setting .. 'n having a bit of go-pedal fun ..

and .. Then ..

i installed that air-intake mod ..

and was very suprised at the positive difference it made to engine performance ..
( initialy i fully expected it to make little if any difference ..
( apart from contracting the time it takes to remove the air-filter housing ..

so .. today .. gave the L setting another go ..
figuring that it might quicken the engine response to the Lower ron-box 'torque' ( below 2500 rpm ) settings
i.e. when taking off from a complete halt .. 1st and 2nd gears .. especially uphill !!
( by 3rd gear the air flow is moving fine so engine response quicker )
and .. it worked just fine

.. the lower rpm range now has the dgb1 'feel' ..
feels a bit like one could easily use a hand lever instead of a go-pedal ..
bit like a power-boat or aircraft ..
( that was the first thing i noticed about the dgb1 ..
( when climbing hills .. little or no go-pedal was needed when the hill got suddely steeper half way up ..
plus that odd engine braking as described above .. but not so pronounced ..
it's a 'useable' oddity

nice thing is there's now a smooth feeling 'curve' from the power delivery .. thru the rpm range

and zero complaints from the engine at v.low rpm when put under load ..
( .. depending on gear selection obviously .. )

am currently under the impression .. pending futher investigation .. that ..
both the dgb1 .. and the intake-mod .. also offer better mpg potential ..

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

 

[Skinny Mike]

@mike .. et al .. re :



it feels to add some extra boost to a part of the rpm range preselected via some mini-switches
( a torque graph might show a bulge coinciding with chosen rpm range )
there's positions .. L / M / M-H / H .. to choose from

with the td4's vnt type turbo .. i imagine the device alters the behaviour of the turbo vanes
one by-product of its' operation .. seems to be .. adding a bit of engine braking ..
i.e. when right foot is let slightly off the go-pedal .. mid cruise ..
but not when foot is 'completely-off-the-pedal' .. as that i assume makes the vanes' angle as 'no-boost'

~~~~~~

i tried all the settings over a few days driving ..

H .. seemed a bit useless for the td4 .. it starts at 2800 rpm aprox.
M-H .. was interesting .. but engine coughed once at passing 2800 rpm under full go-pedal ..
.. and as i didn't want H in the equation .. decided to go with ..
M .. where i spend most of the time in regards to engine rpm ..
.. only issue with M is that the power delivery is 'peaky' ..
.. a bit undesirable ( for me ) when using lower gears in slow traffic ..
.. but .. out on the open ( ha ha ) road .. it's brilliant !!
L .. didn't seem to do much .. consigned it to the 'maybe-good-for-off-road' catagory

i was hoping the L setting would enchance engine response time to go-pedal movement .. When ..
using the lower power setting on the ron-box 2a .. but L setting didn't seem to help ..
so motored on using the M setting .. 'n having a bit of go-pedal fun ..

and .. Then ..

i installed that air-intake mod ..

and was very suprised at the very positive difference it made to engine performance ..
( initialy i fully expected it to make little if any difference ..
( apart from contracting the time it takes to remove the air-filter housing ..

so .. today .. gave the L setting another go ..
figuring that it might quicken the engine response to the Lower ron-box 'torque' ( below 2500 rpm ) settings
i.e. when taking off from a complete halt .. 1st and 2nd gears .. especially uphill !!
( by 3rd gear the air flow is moving fine so engine response quicker )
and .. it worked just fine

.. the lower rpm range now has the dgb1 'feel' ..
feels a bit like one could easily use a hand lever instead of a go-pedal ..
bit like a power-boat or aircraft ..
( that was the first thing i noticed about the dgb1 ..
( when climbing hills .. little or no go-pedal was needed when the hill got suddely steeper half way up ..
plus that odd engine braking as described above .. but not so pronounced ..
it's a 'useable' oddity

nice thing is there's now a smooth feeling 'curve' from the power delivery .. thru the rpm range

and zero complaints from the engine at v.low rpm when put under load ..
( .. depending on gear selection obviously .. )

am currently under the impression .. pending futher investigation .. that ..
both the dgb1 .. and the intake-mod .. also offer better mpg potential ..

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Very interesting. The air intake mod is moving up the list, what are the two sizes of pipe? 60mm+ 45mm??

Had to take the synergy straight back off, it's showing up how badly worn the roll bar bushes are, lots of clunks and bangs.
so it's time to order some bushes, probably go with some poly's. Fortunately its not the main car anymore so no rush.
But it went like a rocket on setting 2, very pleasing after all the eleectrical problems recently.
mike

 

[hd3]

what are the two sizes of pipe?

my measurements .. inside diameters

( original plastic-ducting unit outside measurements )

intercooler ..... 51 mm
egr ............... 57 mm
air intake ...... 70 mm

and .. i retained the offside top intercooler hose ..
alloy tube After the air-temp sensor housing ..
( alloy tube with beading around the ends .. )

and needed a shorter 'straight' alloy on the air-intake ..
compared to the measurements posted in the original thread ..
( so had to cut a bit off )

~~~~~~~~~~~~~~~

 

[Joe_H]

The inlet mod does look nice and should improve response I would think. What MAF are you using Mike?
I think I'm going to sort out the exhaust system next. The cat and rear box are incredibly restrictive to flow. This will really hamper turbo spool up. So next plan is to replace the rear box with a smaller straight through unit. Then I'll look at the cat to ascertain if it's blocked. I'll base what I do next, on the condition of the matrix.
I plan to attack the intercooler with the pressure washer as the core is full of crap. I'll clean out the interior of it at the same time with a good dose of petrol.
So far the TD4 is going well, with increased throttle response. It's not as lively as a V6 but it's not bad for a diesel. It's considerably better on fuel than the V6.

Hi Nodge, It would be unusual to tell from a visual inspection of the cat matrix if there were any performance decreasing blockages - firstly - you only see a small part, secondly, you have no real way of assessing the airflow, thirdly, it is a fact that the cat is detrimental to performance.
I would suggest that you knock the innards out - if needed - buy a S/H cat to keep in stick replace it with if you ever need to due to emissions tightening (highly unlikely especially on a vehicle of this age!)
Removing the cat which is a natural restriction - no doubt about that - even in a new state - is a guaranteed performance upgrade. It allows the exhaust to flow in a far more efficient way, It hence allows the turbo to spool up more rapidly and gets rid of the waste gasses in a more efficient way.
Yes, certainly - there may be a further restriction in the exhaust that can be removed once the main restriction - the cat - is removed - however, removing the cat will give you biggest bang per buck of any mod. (IHMO of course - simply removing the innards of the cat has literally transformed the L series with no other mods (I removed the egr and noticed nada difference - however - I know less crap will enter the intake - so win win.)
Joe

 

[Nodge68]

Binning the cat is on the cards as is replacing the rear silencer with a free flowing alternative

 

[Joe_H]

Binning the cat is on the cards as is replacing the rear silencer with a free flowing alternative

Hi Nodge, the cat is a definite proven restriction - it is a factor of the design !.
Rear silencer - well, yes, but after the cat.

As you well know from your history in the tuning 'game' - one at a time - cat has to go first. - you will be very very happy at the results as - again - it is a KNOWN and definite restriction.
Cheers
Joe

 

[Nodge68]

The affect the cat has on a turbocharged engine is different to that of a NA engine. On an NA engine then the restriction in the exhaust will reduce torque at the flywheel.
A turbocharged engine will still make much the same maximum torque, be it with a cat in the exhaust or not. Torque is made by burning fuel with air. Air pressure is controlled by the wastegate. However the point at where the torque peaks will be lower in the RPM range, when the exhaust pressure is reduced (cat/ silencer removed).
The reason for this is due to the pressure in the exhaust turbine housing. The exhaust turbine must have a higher pressure across it than the compressor housing or energy transfer wouldn't take place. So the exhaust turbine is the largest restriction in the exhaust. Removing restrictions downstream of the turbo simply makes the turbo spool up faster, boosting low RPM torque. It also gives an improvement in efficiency, as less fuel is needed to overcome exhaust and inlet inefficiency.
So yes it's worth removing the cat and any other restriction in the exhaust. But the gains aren't the same as would be seen in a NA engine.

 

[Joe_H]

The affect the cat has on a turbocharged engine is different to that of a NA engine. On an NA engine then the restriction in the exhaust will reduce torque at the flywheel.
A turbocharged engine will still make much the same maximum torque, be it with a cat in the exhaust or not. Torque is made by burning fuel with air. Air pressure is controlled by the wastegate. However the point at where the torque peaks will be lower in the RPM range, when the exhaust pressure is reduced (cat/ silencer removed).
The reason for this is due to the pressure in the exhaust turbine housing. The exhaust turbine must have a higher pressure across it than the compressor housing or energy transfer wouldn't take place. So the exhaust turbine is the largest restriction in the exhaust. Removing restrictions downstream of the turbo simply makes the turbo spool up faster, boosting low RPM torque. It also gives an improvement in efficiency, as less fuel is needed to overcome exhaust and inlet inefficiency.
So yes it's worth removing the cat and any other restriction in the exhaust. But the gains aren't the same as would be seen in a NA engine.

I agree with your generalised description although it is extremely generalised !, - however, I am not concerned in the slightest re a N/A engine - we are talking about a boosted pressure engine - hence the increase is excellent.
I do not understand your references to the N/A engine of which we are not discussing ??? - Improving the increase in spool up speed of a turbo in a boosted (Diesel) engine is a huge benefit. - no denying.- I would also disagree that the gains are less in a boosted engine than an N/A engine - the gains are definitely more.
An N/A Diesel engine simply will not produce the proportional gains as opposed to a boosted Diesel unit by removing the cat - Absolutely Period.
Joe.

 

[Joe_H]

"So the exhaust turbine is the largest restriction in the exhaust"
The turbine is a single part of the system - nothing more - IF it was the largest restriction, then no appreciable gains would be made by reducing restrictions further down the line with a suitable exhaust system. This is simply NOT the case. The turbine is actually RESTRICTED by exhaust system design - specifically on modern engines the cat - far far more than any back box etc.
With a perfect open system (in a diesel!) the removal completely of the exhaust 'system' would leave the turbine housing as the 'largest' restriction - that is the only time the statement is true.
Again, this is NOT the case on an N/A engine where (presuming Diesel) the removal of the complete exhaust system would give little proportional increase compared to the boosted engine.

 

[Nodge68]

What I'm saying is. That I agree that removing the cat to improve flow from a turbo charged engine will increase torque. However that increase will only happen before the wastegate opens. Once the wastegate is dumping excess gas down the exhaust, the engine has reached its limit of power production. No more air is forced in which means no more fuel can be burned= no more power can be made.
However most people don't drive at full power, most of the time, so a very real everyday benefit is to be had.
There's another good reason to remove exhaust restrictions from turbocharged exhausts. It's a general improvement in throttle response and reduction in compressor stall. So removing exhaust back pressure will allow the turbo to spool up faster and help prevent it from slowing down so quickly between gear changes. Both these will make the vehicle faster through the gears.

A NA engine will see most benefit at full power, when most exhaust gasses are flowing.
This is the opposite of a turbo engine, who's maximum exhaust flow volume is controlled by the wastegate.
I only included NA as an example, nothing more.

 

[hd3]

did a 30 mile run today with the ron-box 'fuel' switch turned Off ..
included a couple good uphill acceleration tests ..
( part of a 60 mile daily round trip ..
( driven since before doing any engine mods. ..

conclusion ..
intake mod + digibooster set to ' L ' .. standard stock fuel-pressure curve ..
much the same as .. standard-intake with no digi.b. .. and ron box 'fuel' On the Med / Med setting ( 2 or 7 )
although .. maybe .. just maybe .. a tad less ooomph at the 3k rpm level 'n above ..

next time i'll turn both the ron-box and dgb1 .. Off ..
'n gauge what effect the intake mod has had on its' own ..

~~~~~~~~~~~~~~~~~

de-cat ???????? ..
i'd like to .. but have heard / read .. that it can be shown up if the mot tester
decides to check the cat casing temp. against nearby exhaust parts ..
the cat .. generally runs hotter ..
have tested that with an IR thermometer ..

i'd try a so-called competition cat .. but not sure if they're made for diesels ..
and don't know if a petrol type would suit ..
( i fancy a side-exit exhaust anyway ..
( would like to leave rear window fully open without the smell of exhaust entering
( more for my dog who travels in the back .. than me ..

~~~~~~~~~~~~~~~

 

[Gaj1612]

glad yours is sorted mate.
fixed mine today after replacing one injector (under warranty ) and fitted the inline thermostat also filled her up with shell diesel. seems to be running a lot better now.

am interested in doing the intake mod next along with egr delete. if anyone could give me any info or maybe a how to id appreciate it.

 

[hd3]

am interested in doing the intake mod next along with egr delete. if anyone could give me any info ..

the egr delete is easy .. undo 4 bolts and the mini clamp to the exhaust feed ..
remove the egr valve ..
insert the 'delete' unit .. clamp the exhaust outlet to the fitting provided on the 'delete' unit
tighten bolts .. connect intercooler hose .. job done
the old egr seal can be re-used if not damaged ..

here's some pics explaining what to do with the redundant vacuum hosing ..
https://www.landyzone.co.uk/land-rover/where-does-this-go.223312/#post-2536215

~~~~~~~~~~~~~~~~~~~~~~~~~~~

 

[Arctic2]

I removed the fluff from the filter this weekend. I also tested it's air flow ability, very crudely. Basically I passed air from my workshop vacuum through a piece of the fluff while monitoring the pressure in the vacuum pipe. I was amazed at just how restrictive the fluff is. So well worth removing IMHO.

I also thought removing the nylon/fluff cover of the air filter would damage or at least wear out the MAF quicker I could be wrong ?

 

[Nodge68]

I also thought removing the nylon/fluff cover of the air filter would damage or at least wear out the MAF quicker I could be wrong ?

I removed the fluff as it is actually really restrictive to air flow. Removing it won't make any difference to the filtration as the paper element has much finer filtration properties. The paper has a huge surface area compared to the fluff, so won't clog so fast.

 

[Arctic2]

I removed the fluff as it is actually really restrictive to air flow. Removing it won't make any difference to the filtration as the paper element has much finer filtration properties. The paper has a huge surface area compared to the fluff, so won't clog so fast.

Hi Nodge
Convinced so I will try this at my next service September, I always do a service every autumn & spring regardless of the miles I have covered which is at most 3.5 4000, this October I will have had the car two years bought it with 83000 now it is 88350.