Still struggling with my TD5!

I've had this problem with my TD5 since new (1 year ago) and it still is not right. When you drive it carefully in high range you only have to press the accelerator about half way to maintain 70mph.
If you use full throttle it defaults into a different mode where you then have to press it almost to the floor. Turbo boost is reduced and although it will still do 80+ on the flat it has less power on hills. Sometimes it went into a third even slower mode where top speed was about 70. Stopping the engine and re-starting it resets it.
No fault codes are registered.
the dealer says there is nothing wrong with it.
I looked at the turbo and the paint seal on the rod was broken, there were 13 threads showing on it, I adjusted it to 12 (after looking at another one to compare) and this cured the third default mode described above....
The wastegate lever seems free to move when the rod is off it but only through about 45 degrees...is this right? I heard that it should be 120.
Personally I think that a trip to SUPERCHIPS is looming. (Only because they are based in Stockport near where I live) to see what they can do with the bugger.

I think its being foreced into some sort of limp home mode, which throttles the engine back if its going to go to fast, it would appear your turbo waste gate was altered a bit too much.

I agree on that but how can I know what the correct setting of that threaded rod is? The vehicle was a dealer demonstrator and it's obvious that somebody has tampered with it to make it a bit faster on the cheap.

Can you see any of the original clean - i.e. covered thread?

Turn it back till it works fine, but doesnt go mad.

change it for a 300tdi

My friend just bought a mint 300TDi with only 24k on it and it's superb...no fancy drive by wire dual response throttle/computer controlled turbo rubbish and none the worse for it. In fact it's better.

Get a brand new 300tdi

The TD5 turbo boost pressure is NOT controlled "normally".
Bugger all in a TD5 is normal.

The turbo boost is controlled by the ECU thing, and if the boost goes too high (over about 20psi) it throws you into a limp-home mode of sorts until you stop and start again. 20 psi is not too much boost. More boost means more efficiency means less fuel used and a tad more power

I think a smart-arse has failed to realise how the TD5 turbo works, and has screwed the boost rod "up", thus creating >20psi boost whenever you deck the go pedal. This will instantly invoke limp-home mode. Read the manual. I think even the owner's manual has words on this.

I fitted my TD5 with a boost gauge. £25. It shows 2 two things:-
1. the actual turbo boost as one drives along, and
2. when the ECU starts backing off the boost.

The actual boost is when the needle sits smoothly, thus showing that the ECU has not interfered yet.

When the ECU takes over, the boost needle flutters rapidly as the waste-gate valve is fluttered open and closed by the ECU to drop the boost.

One day soon I will work out a way to keep boost pressure way UP (good idea) without getting thrown into limp-home mode (bad idea).

When I do I will let you know. meantime, get a gauge and fit it.

CharlesY

I fitted the boost guage last night and what happens is that when you apply full throttle the boost goes up and soon reaches 20 on the guage. At this point the boost is limited...you can feel it holding back. This also triggers the slower throttle response mode (where you need more pedal to get the turbo to come in)..it still goes OK but the boost then will stop just before 20 until the engine is stopped and restarted.
Can I sort this out...maybe I need to adjust that threaded rod to reduce the maximum turbo boost?

Well now, there you go. What did I tell you?

As far as I have found out, when the boost goes any over about 20 psi the thing shuts down into limp home wimp mode - until you switch off, and start again.

I suggest some smart-arse has failed to understand that the boost pressure is controlled by the ECU in a TD5, and has screwed the waste-gate rod way too far, allowing it to over-rule the ECU and hit 20+ psi even though the ECU tries to hold it down to about 15 - 16 psi, just over 1 BAR.

This tells the ECU that summat is askew, and it shuts down to limp mode.

I think you want to make the rod LONGER by at least half an inch, and see what happens.

Properly set, at 1800 - 2000 revs or more with the pedal decked, the boost gauge should hit about 1 BAR / 15psi and then the needle should visibly vibrate as the ECU flutters the waste gate valve to keep it under control at that pressure.

When you reach this stage, call it a day!

CharlesY

Going to let us all know how you got on please?

CharlesY

Mine is still doing this as well, l posted on your old thread months ago, but l don't think its to do with the turbo.
What l've found is, if you switch the ignition on and push the throttle to the floor and back once, then start the engine it has the same reduced power effect as flooring it while driving

Rich

Curiouser and curiouser.
I wonder what Eightinavee thinks about this?
I think I will not try this in my TD5 in case it starts a problem (another problem ...)
CharlesY

Yes as soon as I get round to trying again I will let you know. Are you sure that making the threaded rod longer decreases the boost? I've been shortening mine...and one turn (about 1mm) makes quite a difference. I'm not certain there's enough threads on it to try an adjustment of half an inch!!
Trying to sort out the towbar at the moment as I need to tow a couple of big beasts at the weekend.

Have you got a boost gauge yet?

I feel pretty sure the excess boost is the cause of the problem.

CharlesY

Hey there Rottenrich...I remember you from last time. What have you done to yours to try and sort the fault? Have you adjusted or changed anything?

lightning said:

Hey there Rottenrich...I remember you from last time. What have you done to yours to try and sort the fault? Have you adjusted or changed anything?

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l've not done anything l just live with it, it doesn't bother me to much, you just have to give it more throttle.
l tried driving it after pushing the throttle to the floor before every start up for a whole tank diesel and the mpg was still the same, so it seems to just change the response of the throttle l only drive at 55-60 so don't know about top end speed.

We don't drive that fast in ours either but it would be nice to sort it out....just out of interest could you count the number of threads showing on your turbo wastegate rod (mounted just above the turbo) and let me know what you find?

This sounds like a problem a mate had on his TD5. Turned out to be the inlet hose to the Turbo itself. The standard one has an inner and outer skin, and under load the inner skin was collapsing but couldn't be seen due to outer hose. New hose and all was well - Get a decent solid hose like the blue ones that Twisted Performance sell

Take5 said:

This sounds like a problem a mate had on his TD5. Turned out to be the inlet hose to the Turbo itself. The standard one has an inner and outer skin, and under load the inner skin was collapsing but couldn't be seen due to outer hose. New hose and all was well - Get a decent solid hose like the blue ones that Twisted Performance sell

Click to expand...

Good Grief ..... only LandRover could come up with a problem like that!

AAAaaaaarrrrggghhjhhhhhh !

CharlesY