TD5 - poor low down performance

[The_Gods_Must_Be_Crazy]

Hi,

My '01 110 CSW went in for a service at my local specialist and they said part of the engine harness needs replacing as oil is getting into it and then through to the ECU (pool of oil under the seat). It's gone back in today to have this done.

At the same time they said that the engine is flat and should have lots more go.  Its the only TD5 I've driven and I've only had it a year I thought it was normal.  Once its got plenty of revs its fine and pulls as it should do.

They plugged their computer into it and it came up with loads of what they said were odd faults, which they said might be the various currents going from one terminal to another because of the oil and maybe confusing the ECU. They are not sure if replacing the harness will cure it or not.

Does this sound right? And will replacing the harness help?  It's not that I don't trust them, as I've known them a long time and fully trust them. But I'm not used to Landys with all these electronics and can't quite get my head around it, so I'd like to hear if anyone else has any exerience of this.

Thanks,

Dan.

[Porny]

Hi Dan,

Welcome to the Forum  :D


What they've said about the harness is true.

Some Td5's do suffer from oil contamination via the injector harness.  Usually this can just be cured with replacement of the injector harness - which is about £45 from a dealer, and will take less than hour to change.  It is only in rare occasions that you also need to replace the whole engine harness.

If you just clean the red ECU plug out with electrical cleaner (or brake cleaner) hopefully with a new injector harness, and after 4 or 5 times of cleaning the plug you should stop getting oil to the ECU.

In all honesty they do sound a but vague in what they've told you.

The two most common causes of poor low speed performance are a faulty Air Flow Meter (very common) - and doesn't always show up as logged fault on the ECU -  and a partially blocked/open EGR (exhaust gas return valve).
Without sounding like a plug... I can supply replacement AFM's much cheaper than most other people - and I can supply a proper EGR replacement kit.  

The EGR is not needed for anything other than European Legislation which the car must meet at the time of sale... but once in private hands it can be removed - and will not affect MOT's!!

Where-abouts are you?? (your location is blank in your profile)... if you're anywhere near the Midlands (or even the Lincoln, Humberside, Doncaster area) I'd happily have a look for you.... if nothing else just to confirm what you've been told.


Cheers

Ian

[The_Gods_Must_Be_Crazy]

Thanks Ian,

We tried new AFM and it made no difference. What is the EGR? The engine pulls like at train when its revving, but once you change gear it then feels a little flat before going again. It's still quicker than my old 300tdi and everyone I spoke to said they don't quite have the low down grunt of a 300 so I've always thought is was normal. Out of interest it does not really smoke.

I'm North Shropshire.

[Boddle]

Item 12 Located front engine bay driverside (RHD)

a lot of people build a to blank ERG system I believe it goes in the joint to exhaust manifold (8) item (9) split the joint put a blanking plate and reconnect block the Exhausts gas being sent back though the intake manifold.

I have seen blanking plate on E-Bay £2 to £3 if you have difficulty making 1.

Had similar problem with Oil in harness, replace injector harness and cleaned ECU Plug, Engine bay harness will cost about £450, I think a can of WD40 is a lot cheaper.

The rubber seal inside the connector can expand with some cleaners it might be removing before you clean it and it with a clean rag.

[Porny]

Was the AFM you swapped a new one, or a used one??
Did they check the 'live data' page to make sure it was working correctly?

What were the other errors that the diagnostic computer brought up??

A Td5 although different to drive than a 300Tdi, should be just as spritely....


EGR, as mentioned is the Exhaust Gas Recirculation...

Basically a method of recirculating some of the exhaust gas back into the intake so that it gets used again - and thus cleaning up the emissions at the exhaust pipe.
Has a habit of coating the inside of the intake with oily sludge.  :roll:
If the EGR is sticking, it will pass exhaust gas all the time which can effect performance!

I do a kit that includes a blank for the exhaust manifold (correct thickness, unlike most of the ones on Ebay) and a billet alloy section to replace part number 12.  
In doing this you can also get rid of part numbers 9, 14, 2, 1, 17, 16  

Or, if you prefer you could just blank the pipe from the exhaust manifold... but not 'as' good for a few reasons.


Have you also checked the normal stuff?? - air filter, intercooler hoses etc etc.


If every thing is working correctly... and you still want more you could always have your ECU remapped - I might know someone who can do this     But no point if you have faults with your engine.


Ian

[The_Gods_Must_Be_Crazy]

The AFM was a new one.  I can't remember what the errors were as they went straight over my head. I'm going to try and find out as much as possible tonight when I pick it up.

[Boddle]

I do a kit that includes a blank for the exhaust manifold (correct thickness, unlike most of the ones on Ebay) and a billet alloy section to replace part number 12.  
In doing this you can also get rid of part numbers 9, 14, 2, 1, 17, 16  

Sounds like a good way to get rid of EGR altogether

can you give us an ideas how much for the kit

[thermidorthelobster]

If the EGR is the same as the Disco TD5, which I'm assuming it is, you could start by unplugging it, which will give you an idea of whether it's worth blanking off.

[Porny]

If the EGR is the same as the Disco TD5, which I'm assuming it is, you could start by unplugging it, which will give you an idea of whether it's worth blanking off.

That only applies if the EGR is working correctly   .....

Boddle, you have a pm....


Ian

[thermidorthelobster]

If it's not working, then what's the value of blanking it off?  Or, are you saying it could be working (ie valve opening / closing) but not as nature intended?

[Porny]

If you unplug it, all you doing is stopping the vaccuum operating the plunger/or blade in the intake on the inlet manifold.

The problem is, when they get covered in gunk (which they all do!!) they are prone to sticking  - which means they allow a small amount of exhaust gas to be pulled over all of the time.  Just unplugging the EGR will not prevent this.

Although you could just fit a blanking plate on the pipe from the exhaust manifold to the inlet - you might as well do it properly and get rid of restrictive intake at the same time (later spec Td5's are even worse)

Ian

[thermidorthelobster]

I sealed up the hole in mine.  It may not be as ideal as having clear airflow, but it only cost me 10 Norwegian kroner (the coin which happened to be the exact size of the hole which needed blocking).

[The_Gods_Must_Be_Crazy]

Sorry for the delay.

Picked up the motor, complete with new harness.  Still came up with error codes but was told to run it for a week so most of the oil in the main engine loom can come out (keep cleaning the plug at the ECU), then take it back next week to see if they can reset the error codes.  He was pretty sure that the oil in the loom was the cause of the problem.

Just got to wait and see.

[Porny]

Sorry for the delay.

Picked up the motor, complete with new harness.  Still came up with error codes but was told to run it for a week so most of the oil in the main engine loom can come out (keep cleaning the plug at the ECU), then take it back next week to see if they can reset the error codes.  He was pretty sure that the oil in the loom was the cause of the problem.

Just got to wait and see.

Fingers crossed then...

If you ever wanted a second opinion i'm not 'that' far away  

Ian

[Boddle]

Boddle, you have a pm....


Ian

 ? wasn't quite sure what you mean
Sorry I haven't looked at site couple of days (work) are you suggesting an evening

[Porny]

Steve...

Sorry - it means you have a private message  

Have a look at the top of the page (to the right of the mud-club logo) - it should say either log in to check your messages, or you have 1 new message.


Cheers

Ian

[graemeELLIOTT]

check your map sensor, mine was minging!
situated on inlet manifold, clean crap off with brake cleaner

can i also recommend gary at www.td5alive.com

[The_Gods_Must_Be_Crazy]

Update time:

Went back yesterday and and the fault codes have gone, except one - 'driver demand circuit'.  My landy specialist thinks this is still down to oil in the main engine harness as it comes up as an intermittent fault.  His suggestion is because its not that bad and I had not noticed the problem before, to run the motor for a couple of months, still cleaning the oil that will come out at the ECU and if it does not cure itself, then look at the throttle pedal. Rather than spend more money straight away on a new throttle pedal.

Graeme: STW'ers here!

Where's this map sensor? I might clean it anyway.

[Porny]

The map sensor is on the side of the inlet manifold...  the mounting is circled in the below picture  

Driver Demand problem...

Could be a couple of things, and not always the throttle pedal in my experience.

If you did want a spare throttle pedal to try - let me know  


Other problems that cause the same fault:

Plug not correctly clipped in place on the throttle pedal itself (was quite common at one point) - would be worth unpluging, giving it a clean and making sure it clicks in place correctly.

And a fault in wiring from the ECU to the pedal - I've known this to occur a couple of times.  Easiest method of fixing it is to make up a new mini loom from the pedal to the ECU... and problem fixed  



Ian

[graemeELLIOTT]

STWers here?

[The_Gods_Must_Be_Crazy]

STW - SingleTrackWorld

[graemeELLIOTT]

ah!
wakey wakey Graeme

Yeah santascruz on there

[The_Gods_Must_Be_Crazy]

A rocky mountain here, and a spesh road bike, but i try and keep that quiet  :oops: