TD5 - recent Turbo Lag!

[5teve]

Hi Guys

just drove home and noticed the Disco II TD5 was a bit lumpy accelerating. just nothing and then everything a second or so later.. so been playing all the way back and something is wrong...

if i drive carefully (ie accelerate at slow rate so turbo can spool up) then all is good.. if i hit the loud pedal fast (at around 2000rpm) then you can feel the engine trying and a second or 2 later bang... loud pedal kicks in and a cloud of soot comes out the back... and you get thrown back into the seat... its as tho something is stopping the turbo from spinning up properly..

any ideas? stuck wastegate, collapsed (or nearly) intercooler hoses, blocked airfilter?

by the way its got one of tombraiders programs running and has been impecably for about 9 months..

thanks

Steve

[Slunnie]

I noticed this with mine recently and it turned out to be a blown MAF sensor fuse (under the bonnet, 2nd blade fuse from the front). The wiring runs under the engine cover from the passengers side and the split tube had perished that covers it which resulted in a short. When split tube was replaced and the fuse replaced also it seemed to fix the massive lag problem.

[tombraider]

Agree with Slunnie...

OR...

Split modulator hose
Jammed wastegate (slightly open)
Failed MAF

OR, the common one...

The plug on the MAF has come away or not making contact on each pin correctly.

[DougLD]

Hi All
It could be the hoses from the turbo being sucked in and not getting enough air through.
Regards
Doug

[tracker]

or it could be crap diesel same as we get here quite often:mad:

[5teve]

Hi guys

just taken it on a short run and its gone... inlet hose into the intercooler is soft as :toilet: so im wondering if when heated it is collapsing..

i'll check the rest of the stuff... thanks guys.. probably tomorrow..

how do i know if the wastegate is stuck?

thanks

Steve

[Blknight.aus]

to check the waste gate unhook the pipe that goes to it and using a regulator on an air compressor wind up the pressure till its fully open. pop the airline on and off a few time rapidly and eyeball it for any irregulat motion or increase in motion.

Thats only a field check and not overly accurate if its being held open by carbon build up on the valve face or a bent/distorted shaft.

it can also be the EGR system not closing up properly for some reason and then closing or if you have the butterfly EGR (im not sure when they started that lark) the butterfly might be lagging till you get enough boost to snap it open.

[DEFENDERZOOK]

ive been having the same problem but i put it down to bad fuel i picked up in albury last weekend......

i then added more fuel.....proper stuff not bio........and it made a huge difference......
however....as its still got some of the bad fuel mixed in with the good stuff.......im hoping its gonna get better when i have to refill this weekend......


the symptoms im suffering are the same as what you described in the original post.......
but im also suspecting my egr valve.........

as for the intercooler hoses collapsing........arent they under pressure when on boost.......
or are we talking about collapsing before boost kicks in.......

[Graeme]

ive been having the same problem but i put it down to bad fuel i picked up in albury last weekend......

i then added more fuel.....proper stuff not bio........and it made a huge difference......
however....as its still got some of the bad fuel mixed in with the good stuff.......im hoping its gonna get better when i have to refill this weekend......


the symptoms im suffering are the same as what you described in the original post.......
but im also suspecting my egr valve.........

as for the intercooler hoses collapsing........arent they under pressure when on boost.......
or are we talking about collapsing before boost kicks in.......
The hoses delaminate and the inside layer splits and flaps under pressure whilst looking OK from the outside.

[Blknight.aus]

ive been having the same problem but i put it down to bad fuel i picked up in albury last weekend......

i then added more fuel.....proper stuff not bio........and it made a huge difference......
however....as its still got some of the bad fuel mixed in with the good stuff.......im hoping its gonna get better when i have to refill this weekend......


the symptoms im suffering are the same as what you described in the original post.......
but im also suspecting my egr valve.........

as for the intercooler hoses collapsing........arent they under pressure when on boost.......
or are we talking about collapsing before boost kicks in.......

typically they dont go wrong till they go soft and then they have 2 maybe 3, depedning on your take on the failure, methods of failure

the first is when the heat delaminates the hose and turns it into a kind of flap valve. This can go away when the flap folds over or when you back off and go again as the flap opens up and stays clear. Once this one starts happening its just going to get worse

the second is when the hose collapes from the engine trying to draw more air than the turbo can deliver so the external atmospheric pressure crushes the pipe, when the fuel supply backs off the pressure differential changes the pipe opens and if your lucky stays open once the turbo spools up and boost pressure keeps it open. the other side of this is at boost they bulge and begin to leak a little before splitting so if you get a hose split and the problem goes away when you replace it this was the culprit

and the 3rd one IS when the insides delaminate like shrapnel and slowly fill the intercooler with rubber bits which block off the cross pipes slowing the initial airflow till the turbo gets itself sorted... This one is usually there all the time and can occasionally be identified by the wastegate being fully open even tho the MAP is indicating less than max pressure in the manifold.

pulling your EGR valve out and having a look at it will let you identify if the EGR is clagged and might also have some bits of rubber in it from the intake side of the intercoolers hose.

[DEFENDERZOOK]

thats a very in depth explanation........

thank you......

[5teve]

As always guys i really appreciate your help,

firstly deffo not fuel there is only one supplier of bio over here and i avoid it like the plague.. and it happened halfway through a tank but thanks DZ

EGR valve could be likely as its intermittent.... and its on the list if things to hit... so not long now till its disabled..

im thinking at 112k that the intercooler hoses wont harm anything if they are replaced... and being very very soft on the turbo side im suspecting also that this could be it as i have noticed when the torque convertor is locked up and i boot it it pulls like mad for a second and then dies off as tho its run out of steam.... been like that for a few months now tho... another thing on the list of things to do....

im also wondering if it could be related to the dash problems im having... not every time but quite often whn starting i get like a reset on the dash... or the instruments go hard in reverse and the lights reset... it has done it a few times for a minute or 2 and has done it a long while after start up too... probably not related tho!

anyway will check out tomorrow or on that way to take sis in law (yay) and family in law (boo) to the airport on sunday!

thanks muchly once again

steve

[agrojnr]

When I changed my intercooler hose's I got a bit more power out of mine (I went silcone way)


Adam

[stock]

gentlemen dont know if it will help but I think the problem is related to the wiring loom feeding the injectors engine oil damages the cables which causes minute delays in signal transfer from the ecu .LR recommend that they be changed every 64k-km and are available form a bermark/britpart supplier for 40-50 euros ,also look at a cat replacement pipe alot of horses available there

[5teve]

been there done that and modified the harness too... so im pretty sure its not that, and the symptoms are normally rough running and misfire... or other wierd things!

stacks of info about the harness if you search too...

Thanks

Steve

[stock]

what way is the charge pump?

[trev]

Hi Guys

just drove home and noticed the Disco II TD5 was a bit lumpy accelerating. just nothing and then everything a second or so later.. so been playing all the way back and something is wrong...

if i drive carefully (ie accelerate at slow rate so turbo can spool up) then all is good.. if i hit the loud pedal fast (at around 2000rpm) then you can feel the engine trying and a second or 2 later bang... loud pedal kicks in and a cloud of soot comes out the back... and you get thrown back into the seat... its as tho something is stopping the turbo from spinning up properly..

any ideas? stuck wastegate, collapsed (or nearly) intercooler hoses, blocked airfilter?

by the way its got one of tombraiders programs running and has been impecably for about 9 months..

thanks

Steve

I had the same trouble recently.Turned out to be the turbo valve diaphram perished.
You will see the valve just under the air intake tube held on by two small bolts.It has 2 small hoses connected,one which goes to the wastegate actuator.Check that the hoses are o. k.If you disconnect the valve and can blow through it,the diaphram is gone.
New part is approx. $60.

Cheers....Trev.

[LandyAndy]

Hi Trev
I have a new spare one of these.
I just checked it,with no power connected you can blow thro the lower inlet port and it blows thru to the wastegate port.
Im thinking the 12v power supplied by the ECU closes the valve stopping you being able to supply air pressure(BOOST) to the wastegate,the ECU should open the valve to supply boost to the wastgate to open it at the correct boost level.
With your blow test did you have it plugged in and ignition on????
Thanks for the post,I will fit the newie and let you blokes know how it goes.
Andrew

[LandyAndy]

Ive just replaced the part Trev mentioned as I had a spare.
It actually does go a bit better,perhaps it was faulty.
The turbo sounds better,low end is improved,towing will really show it up.
I belive I still have problems,will see if I get some fuel economy back.
Fairly convinced my MAF sensor is faulty.
Andrew

[5teve]

thanks guys for the info will look at them all

Andy.. what were your symptoms? i have noticed my economy had suddenly seemed to go bad... but i was guessing a ton and a half of boat on the back wasnt helping too much.. but to take out 250k's from my normal tank of 750 - 800k's over a tow of 240k's seemed a bit much... (i ended up with 550k's to the tank) also seemed to be smoking a bit towing it.. (which i guess is where the fuel went)

so over the weekend i have been watching it. All of saturday i was having my dash problem - dead for 30 seconds to a minute every time on startup.. but at no point did i have the lag problem..

yesterday we took the boat out.. towed it to the city... didnt seem any lag problems and only had one instance of dash resetting while driving. but i had the lag problem first thing (4am) going to the airport.

this morning started the car.. dash on 20 seconds later.. and laggy all the way down the freeway.. sitting at 2k rpm boot it and get a small increase for a second then my head got torn off.. interesting thing is that if you do it when the torque convertor is locked the boost causes it to slip as tho it is over boosting.. however it doesnt do into limp mode so not overboosting that much..

also once the boost has kicked in there does seem to be enough power.. and if you accerate slowly enough then the power comes on ok..

due to the intermittentcy of the problem i would be guessing a sensor or a semi stuck something somewhere..

i guess i best get shopping for ...

silicon hoses
egr blanking kit
turbo valve diaphram
some magical fix for the dash problem!

Thanks

Steve

[LandyAndy]

Hi Steve
Mine is slow till it builds up a head of steam,600 to 700 max from a tank,was 800 to 1000 once upon a time.
The wastegate is opening closing(not stuck).
With a trailer on in hot weather its real sad,used to pull my big tandam trailer with 2 tonnes firewood easily,would be a real struggle now.
My 235/85 tyres wont help the situation,but dont belive they are the only cause.

Andrew

[DEFENDERZOOK]

Hi Steve
Mine is slow till it builds up a head of steam,600 to 700 max from a tank,was 800 to 1000 once upon a time.
The wastegate is opening closing(not stuck).
With a trailer on in hot weather its real sad,used to pull my big tandam trailer with 2 tonnes firewood easily,would be a real struggle now.
My 235/85 tyres wont help the situation,but dont belive they are the only cause.

Andrew



have you chcked to make sure you are getting full throttle.......?

[LandyAndy]

I would love to Tony
But the only way is with a new fly by wire isnt it????If there is another way,let me know ready to try anything.From lots and lots of posts the AFM always comes up.
Im ready to buy a newie just to rule the thing out.At least I will have a spare if its something else.
Andrew

[Graeme]

Hi Steve
Mine is slow till it builds up a head of steam,600 to 700 max from a tank,was 800 to 1000 once upon a time.
The wastegate is opening closing(not stuck).
With a trailer on in hot weather its real sad,used to pull my big tandam trailer with 2 tonnes firewood easily,would be a real struggle now.
My 235/85 tyres wont help the situation,but dont belive they are the only cause.

Andrew
Something to be aware of...

If the ecu has initiated fuel cut-out due to excessive boost, then even after the offending part is fixed/replaced, the ecu will not allow more than base boost (via the wastegate modulator) until the excessive boost fault code is cleared. ie only 1 bar boost compared with about 1.3bar.

[LandyAndy]

Thanks Greame
Once I get a new AFM I guess a computer clear is a good idea.
Last time it was wiped they had never seen so many faults.
I had a head gasket and oil in the harness in 1 hit.Most of the faults were put down to the oil.
Andrew

[DEFENDERZOOK]

I would love to Tony
But the only way is with a new fly by wire isnt it????If there is another way,let me know ready to try anything.From lots and lots of posts the AFM always comes up.
Im ready to buy a newie just to rule the thing out.At least I will have a spare if its something else.
Andrew




oops......

i think im confusing threads.......
i was thinking tdi for some reason.......and yes......its really been a monday for me today.....can you tell...?

[Blknight.aus]

Last time it was wiped they had never seen so many faults.
Andrew

yep agree with a lot coming from the oil in the harness thing but a dodgy earth in conjunction with that can cause pure bedlam for the ecu log.

[trev]

Hi Trev
I have a new spare one of these.
I just checked it,with no power connected you can blow thro the lower inlet port and it blows thru to the wastegate port.
Im thinking the 12v power supplied by the ECU closes the valve stopping you being able to supply air pressure(BOOST) to the wastegate,the ECU should open the valve to supply boost to the wastgate to open it at the correct boost level.
With your blow test did you have it plugged in and ignition on????
Thanks for the post,I will fit the newie and let you blokes know how it goes.
Andrew

Sorry for not getting back sooner.Yes voltage needs to be applied.
Unless you have super lungs the valve should not open from the lower turbo pipe input until an over-boost situation occurs which will be over 1 Bar at least.

trev.

[Graeme]

Sorry for not getting back sooner.Yes voltage needs to be applied.
Unless you have super lungs the valve should not open from the lower turbo pipe input until an over-boost situation occurs which will be over 1 Bar at least.

trev.
The modulator, when operating correctly, allows the high pressure line from the turbo outlet to pass through to the wastegate actuator so that the wastegate will open at around 1 bar unless the ecm supplies a (pwm) signal to the modulator to partially dilute the high pressure with low pressure from the turbo inlet so that the high pressure can go higher. The ecu will allow under certain conditions a maximum pressure that equates to about 1.3 bar at the turbo outlet with a std intercooler (mine dropped by 2psi at the turbo with an i/c with better flow).

[5teve]

Hi Guys

right been messing around and also on the phone to Landyandy (cheers for your time andy)

i have cleaned the MAF sensor as it was pretty mucked up.. mainly with dust and an oily film.. which i assume comes from the wastegate modulator pipe that enters the intake pipe on the turbo inlet side of the MAF.

having spoken to andy and talked through how the thing should work i started testing and found the following.

when idling if i take the pipe off the air intake pipe nothing comes out... and if revved also nothing comes out so no air is bypassing the wastegate actuator.

if i take the pipe off the wastegate actuator and do the same thing then air comes out (proved by hooking up to a balloon)

now from my understanding (which is normally wrong) in situations like idle and no load revs air should be directed away from the wastegate actuator? or is it the opposite.. so that the pressure builds up until the point where the pressure is high enough to actuate the wastegate?

sorry if i am being dumb.. its a whole new thing to me..

if its working wrong then i need to get a new wastegate modulator (cheap) if its not then its even cheaper! :D

Andy any chance you could check the operation with your new modulator? please?

then next step is check EGR and probably dump it and blank it!

Thanks guys

Steve

[LandyAndy]

Hi Steve
Will do over the weekend mate.
Im looking at getting a nanocom from Rovacraft that Stuart is doing the deal on.I already need a ECU wipe so thats $100 towards it already!!!!
Andrew

[5teve]

Hi Steve
Will do over the weekend mate.
Im looking at getting a nanocom from Rovacraft that Stuart is doing the deal on.I already need a ECU wipe so thats $100 towards it already!!!!
Andrew

Hi Andy

Already ordered from Stu so will have one soon hopefully... if you dont get then if we are down that way or your up here.. then your welcome to have a plug in of it and see what can be seen!

I have replaced the wastegate modulator today... seems smoother with a bit more power, and once convertor is locked it doesnt accelerate hard for a second then slow down a bit (as tho the wastegate opens) like it did before. it starts accelerating and keeps on going.. however the drive back tonight it seemed down on it again (but rach was driving so who knows, she has avery light right foot) i'll keep testing but i feel like its not just that that is the problem... maybe EGR is the next hit... should be able to tell from the nanocom?

hopefully you get one... and hopefully you sort your probs out.

Thanks

Steve

[LandyAndy]

Ive ordered 1,soon as its in Im straight up to collect it!!!!
Andrew