TD5 lack of power under load.

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Thanks guys.

It appears my local factors sold me Dexron II for the car when it should have been at least Dexron IID. The Haynes manual does actually say Dexron IID or Dexron III.

Best get it changed asap and hope there is no damage.

Glen.
 
Hi there it's Dave again. I'm still thinking this is a gearbox related problem. I want to give you some basic info and then a couple of tests.

Basic info: - the TD5 has a 4 speed electronically controlled auto gearbox with Torque Converter (TC). The TC locks up in 3rd and 4th gear at varying speeds dependant on throttle demand. On light throttle in 3rd at approx 48mph and in 4th at approx 55mph. Once TC lock-up is in place the revs should stay much more closely related to road speed, rather than that "clutch slip" feel of of spilling revs.

Test: - Find a quiet piece of road and with the engine and gearbox warmed up, select 3 and drive up to 50 mph then ease off the throttle until you have just enough to maintain speed. It should now go into TC lock-up - which feels like it's selecting the next gear and the revs should drop approx 600rpm. Does it do this?

Then select D and drive up to 55-60mph and ease off the throttle to just enough to maintain a speed above 55mph - again it should feel like it has selected a form of overdrive (it hasn't it's just the TC locking up as it should).

What results do you get with these tests?

Dave

Dave,

Tried this today and although I had definite TC lock up in D, I could not get it to do the same in 3. To be fair the roads were a bit busy and I had my parents in the car, so I need to try it again to make sure.

Glen.
 
Dave,

Tried this today and although I had definite TC lock up in D, I could not get it to do the same in 3. To be fair the roads were a bit busy and I had my parents in the car, so I need to try it again to make sure.

Glen.


Hi Glen, if it did it in D (4th gear); it should do it in 3 under the right conditions, at about 48-50mph.

Good luck

Dave
 
A quick update on this thread.

The car has been driving fine for the past couple of weeks but yesterday I had to tow a gross weight of about 1250Kg up a fairly steep hill, it held one gear at about 3000 RPM and was struggling to do 20 MPH. About halfway up the hill the ATF temperature warning light came on, and it took about another half a mile to go out.

No fluctuation in revs recently, even towing up this hill.

I have ordered 10 litres of Fuchs Dexron IID and a new autobox filter, so I will try 2 part changes of fluid, as per the dicovery2 web-site, and see if that helps.
 
An update on this.

I did one ATF fluid change with no noticeable improvement.

The car then began to exhibit the same problems up slightly less steep gradients and more frequently as well.

I took the car to Keith Gott Land Rovers near Alton, they read the fault codes and it came up with turbo overboosting, again. They think that the wastegate had been sticking, causing the overboosting and making the engine management system back off the fuel. Hence the loss of power under load, and the apparent fluctuation in revs. This probably also explains the strange behaviour of the auto 'box and the 'insufficient torque' error code.

Will see how it drives over the next few weeks.
 
Hi guys, I'm new to this and flick through all the time, find it very useful. I'm having a similar problem with my disco 2, it's a automatic TD5. I can put my pedal right to the floor and it lacks so much power and seems as if the turbo doesn't want to kick in at all? I've checked the wastegate actuator and control valve, they're both fine, also check the maf, the readings are fine but I've been told the readings can still be fine but get dirty inside, would really appreciate some advice.
Thanks
 
Dirt would affect the readings so as long they are fine it's OK, though what do you mean they are fine(55-60 at idle and above 500/around 600 aunder full throttle)? cos if they were fine you should have boost too or if the air flow is good but the boost is low there's a boost leak somewhere or the compressor side of the turbo has a a problem...do you still have EGR and catalyst(if it's Eu3)?
 
Dirt would affect the readings so as long they are fine it's OK, though what do you mean they are fine(55-60 at idle and above 500/around 600 aunder full throttle)? cos if they were fine you should have boost too or if the air flow is good but the boost is low there's a boost leak somewhere or the compressor side of the turbo has a a problem...do you still have EGR and catalyst(if it's Eu3)?

Thankyou for the reply sierrafery,
At idle the readings are fine, I got advice from land rover and told me to do a reading ignition on and also a reading engine started... the EGR is still on the car, I have been advised to clean it or even blank it?
 
If you saw the reading only at idle it's far from knowing much, then first of all clean or better bypass the EGR and clean the MAP sensor(in the inlet manifold) cos that's certainly full of gunk, is it Eu3 engine with caytalyst?
 
If you saw the reading only at idle it's far from knowing much, then first of all clean or better bypass the EGR and clean the MAP sensor(in the inlet manifold) cos that's certainly full of gunk, is it Eu3 engine with caytalyst?
I'll give that a clean tomorrow and yes I'm sure it is
 
Fitted a new MAF and new wategate modulator last night and took the car for a run up the same steep hill this morning.

The problem is stil there, in D it gets to just under 3000 RPM (about 50-55 MPH) and the revs drop about 100 RPM rise and then drop again, the car is in 3rd gear at this point. Putting it in 3 makes no difference but if I select 2 the revs rise to just under 4000 RPM and it will accelerate again.

Will have to get some fault codes recorded, as I am now rather stumped!
Wastegate issues. Check the wastegate actuator isnt notchy and that the solenoid is working correctly (or bypass it). Another issue could be a dodgey MAP sensor, the vehicle is overboosting (or thinks it is) so bounces the revs at about 3000rpm (or when under heavy load and the pressure hit 1.4bar). Quite common

I would also recommend checking your intercooler to see if it has "ballooned" at the top and bottom as this often happens when driven under lots of heavy load with lots of overboosting as its only designed to withstand up to 1.4bar maximum before it deforms and leaks. Another tell tale sign will be oil leaking out the turbo side of the intercooler housing (where the plastic coupling meets the heat exchanger)
 
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Really need some help and advice! My disco 2 is lacking severe performance than it used to! I've checked all areas from the EGR valve, MAP, MAF sensors, changed the turbo control valve, checked the actuator, all pipes to see if any are split, corroded etc, please can someone give me some advice as to what I can do!?!
When revving the car seems to hum really loudly like air is being released, also when putting foot pedal to the floor! Can't seem to find any air leaks!
Really appreciate any info and help.
Thanks
 
Wastegate issues. Check the wastegate actuator isnt notchy and that the solenoid is working correctly (or bypass it). Another issue could be a dodgey MAP sensor, the vehicle is overboosting (or thinks it is) so bounces the revs at about 3000rpm (or when under heavy load and the pressure hit 1.4bar). Quite common

I would also recommend checking your intercooler to see if it has "ballooned" at the top and bottom as this often happens when driven under lots of heavy load with lots of overboosting as its only designed to withstand up to 1.4bar maximum before it deforms and leaks. Another tell tale sign will be oil leaking out the turbo side of the intercooler housing (where the plastic coupling meets the heat exchanger)

Simon098 really sorry for the late reply, I've recently checked all what you have said and all seem ok, no issues at all, it seems like there's air escaping when putting foot on pedal and not enough power getting to where it needs to?
 
Have you got the chance to run it on live diagnostics i.e.Nanocom when driving it?

That may help point you in the right direction.

Cheers
 
If I was you I would ask around and see if anyone local has one that they will plug in and go for a test ride with you.
A nanocom runs at about £360 at the moment.

Cheers
Wow not cheap then, that's my best hope to see if a local mechanic has one... would other diagnostic tools work?
 
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