Td5 conking out

10 year old 110 doublecab p/up, 130K miles. Owned it from 80K miles, run smooth; serviced 8K ago, 100 miles per day easy running

Parked for 2 weeks, facing up hill, full tank.

Started it - it revved up then died. wouldn't re-start.

Purged (pump 5 times). Started, but ran tremendously rough, noisy... then died. turned over, flattened 10 year old battery. Been meaning to replace that, so did.

Cleaned infamous red plug with Isopropyl alcohol and airline (there was plenty of oil)
Day 2 Turned over, no start. Purge again. start, plenty of smoke, settled down to steady tickover: 5 mins. Blip throttle - engine revved, then died. Wouldn't restart. purge again (5 pedal pump thing).

Starts, ticks over, but slightly rough when revved. Nevertheless, pulls up steepish drive, but doesn't want to rev. Drive for half a mile - takes a while to get to 30mph. Engine light comes on - dies whilst driving. Turnover - no start. Leave it 2 mins - fires up straight away, but doesn't really want to rev.
Drive another 600 yds - dies. Turnover - no. leave it 2 mins - starts straightaway. Dies up the road in middle of traffic lights. won't restart at first - after 3 mins, starts, travels 50 yds and... dies.
Same routine - got it home. Never managed more than 30 mph; and revving it seemed to kill it faster.

Pump sounds fine (same whine as always, no gurgling).

It sort of feels like fuel starvation, and resulted from standing.

What to try next? answers on a postcard...

if engine light came on it has a fault code stored, you need to have that read,
not wanting to rev could be throttle pedal potentimeter,
but if ecu plug was full of oil, Id start by changing the injector loom as that causes loads of issues

Did you check inside the ecu for oil?

Bromsgrove Defender said:

Did you check inside the ecu for oil?

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good point - no I didn't - it's not actually easy to open them up, is it? - seem to remember they are stuck as well as screwed together? is it feasible to just take it off and drain it,, or would that take months?



Think that must be first port of call

ps it's not the throttle pot, as it will actually rev some when not under load - and anyway, that cutting out after wouldn't be that.

I was thinking it seemed like fuel starvation/constriction,, but the ecu is logical (especially as it was parked facing up a steep hill, so 2 weeks of a syphon effect could have helped the oil along the loom

Before taking your ECU apart.

Just check the integrity of the connectors in the black and red ECU plugs, I found I had a loose one..............

Loadsa stuff it could be but I don't think you can rule out the throttle pot totally.

Oil in the loom does cause issues, no doubt... BUT t'int the only cause of cutting out and rough running,. that'd make life tooo easy

Just a bit to add to this:

Having just driven it about 8 miles to Hathersage to a chap I know who fixes all the local farmers' landrovers:

Start on the key instantly. Tickover, sweet as anything, for ten minutes. Blip the throttle...dies. turn it over straight away- won't catch. Stand for 2 mins - starts straight away.

Very, very gently pull away - fine. up the road, hitting the high 20mph figures, back off the throttle a bit - dies. same rigmarole

This continues all the way, with me on hazard lights always looking for somewhere to dive out of the way (with no power steering or servo brakes, so need to be a teeny bit careful) - managed (miraculously) not to inconvenience too many trucks and buses. I came to realise that it was generally whenever I eased off the throttle that the engine light came on and the engine died.

So the last 3 mile downhill stretch - I managed by coming down at <20mph, constant throttle, using left foot braking for bends. As long as I didn't chicken out with the right foot, it was OK, but the slightest sign of weakness and it conked.

All-in-all, an interesting and unusual way to see the Peak district on a sunny day. And the two cyclists who travelled the same route beat me.

I'm thinking something peculiar with the (admittedly leaking slightly) FPR...

sparg said:

I'm thinking something peculiar with the (admittedly leaking slightly) FPR...

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Yup that could do it too

Bit of a fiddly job.... specially if you have large hands

yep. First off, have a look at what the fault codes say, I think

Right, quick update.

still no go - garage bit baffled.
Changed FPR and fuel filter (needed both anyway). exactly same - will tickover all day, but rev it and it dies - actually, it is specifically if you back off the throttle - even a miniscule amount; engine light comes on, engine dies, vehicle won't restart for a few minutes. (pump running fine)

So what control signals and sensors are used when one backs off hte throttle that would be interpreted by the ecu as a fault requiring shutdown?

So what control signals and sensors are used when one backs off hte throttle that would be interpreted by the ecu as a fault requiring shutdown?

Maybe a bad signal from the crank position sensor, but just guessing

I take it, it behaved it'self for the garage then, showing no faults and not cutting out?

Johnlad maybe right about a bad signal from the crank position sensor.

Just be aware it may not be the actual sensor at fault

Have you noticed if the red LED is flashing when it has cut out?

No, the vehicle did exactly the same at the garage - ticked over for 30 mins, but then a blip of the throttle stopped it.

Now, as for diagnostics - I think they were a bit overwhelmed with fault codes (not least all the codes that come up for things it hasn't got, Like AC or ABS). Unfortunately, their diagnostic doesn't provide a printout, so Might have to nip down and photo the screen next. time it's one.

I still have a notion that, because it turned into a nutter after being parked facing up hill for 2 weeks, and there was oil in the red plug, and it's done 120K in 10 years, then most likely is oil actually inside ecu (ecu is a bit of a pain to open, stuck with that white stuff I seem to remember) - OR - abrasion of main engine loom (£350+..!) plus contamination by aged, conductive oil = intermittent or even permanent shorting of certain engine management signals - which unfortunately might mean that ecu signals are garbled, making diagnosis via diagnostics readouts improbable - Does that sound about right?

Now, not wanting to diminish the kids' meager inheritance by buying parts 'till the problem goes away, I'm trying to work out a sensible diagnostic method to rule out (or in) the first, most likely culprits.


Would I be right in thinking that, although the injector harness is the cause of the oil capillary action along the main engine harness, the symptoms I've actually described wouldn't actually be substantially fixed simply by swapping the injector harness? (i.e. the oil is causing faulty signalling elsewhere)?

does it do the same when the fuel cap is removed. We had a car that had a blocked vent on the cap causing the tank to vacuum, which caused similar problems to what you have described.

Rasher said:

does it do the same when the fuel cap is removed. We had a car that had a blocked vent on the cap causing the tank to vacuum, which caused similar problems to what you have described.

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Thanks - I've had that before! - but this is absolutely instantaneous - even a fuel starvation problem would have difficulty acting that fast. In fact. you can actually hold it, revs on, for ages - but if your foot tires and you back off even minutely - engine light on and dies.

Not sure about LED flashing, I must admit - have to check that

Because the check engine lamp comes on as it dies there should be a code logged.What needs to happen is to clear all present codes,restart and recreate the fault.Then re-read the fresh code/s.
A couple of points to note.... Firstly a generic scanner will always show faults for things that are not there - A/C or ABS etc. Its just because the scanner is not specific to LR products.The same car on Testbook will only show actual logged faults that are relavant to that specific layout.
If the garage is scared of reading the codes or is not au fait with ghost codes then you need to find a decent LR specialist.
TD5's have been around a long time now,most faults have shown up enough times to be well known by LR independants - one thing that is showing more often now is engine ecu's dying of old age.So if everything else checks out, we often sub over a spare ecu to test.(Dying ecu's sometimes cant log codes)

eightinavee said:

Because the check engine lamp comes on as it dies there should be a code logged.What needs to happen is to clear all present codes,restart and recreate the fault.Then re-read the fresh code/s.
A couple of points to note.... Firstly a generic scanner will always show faults for things that are not there - A/C or ABS etc. Its just because the scanner is not specific to LR products.The same car on Testbook will only show actual logged faults that are relavant to that specific layout.
If the garage is scared of reading the codes or is not au fait with ghost codes then you need to find a decent LR specialist.
TD5's have been around a long time now,most faults have shown up enough times to be well known by LR independants - one thing that is showing more often now is engine ecu's dying of old age.So if everything else checks out, we often sub over a spare ecu to test.(Dying ecu's sometimes cant log codes)

Click to expand...

Ah thanks. One problem I have is that the vehicle won't move, of course.
But, although the garage where it is are probably more up to date on TDi than TD5s, they do handle quite a lot of TD5s and some Pumas.

As you say, clearing the codes shouldn't be a problem, and the ghost codes should be readily spottable. So clearing the cides, reproducing the fault then simply ignoring ghost codes ought to narrow it down a lot.

I'm interested in this notion of old ecus dying - whilst I wouldn't think of 117K miles as old, perhaps 10 years is (though I'd consider it unacceptable). What cause this dying? - Oil, moisture, drying out of solder, - what is it? - I'm interested because, if the fualt were not the ECU, and one used a generic spare ECU for test purposes, could an engine loom short (for instance) put the test ECU at risk? (could be an expensive test then!).
Finally, if I'd excluded most everything else, how would I go about obtaining a spare-for-testing? - simple sale-or-return basis?
regards

Although you say they do alot with TD5's etc - it doesnt mean to say they will get to the bottom of a fault like this.Many garages shy away from proper diagnostic work as it can be time and mind consuming,which cant always be charged for.So many will only go so far or do quick,known fixes etc.
As for a loan ecu,I have used Allcar electronics from Alfreton before when I needed an engine ecu for an MGF with the VVC engine. They set up the ecu so it wont need security coding,it will just run on any car.(This is so people without dealer spec diagnostic kit can swap ecu's over)They do a deal where you loan it for a week or keep it,they charge you accordingly.
Saying that, I dont want to lead you up the garden path of it "must be the ecu",if it were in my shop I'd be first looking at codes then using an oscilliscope to monitor in real time what is going on - that is the proper way to sort this out.

Yep, clear the codes to start with, then see what comes up on retrying.

But what does make the ecu die?

Dont know,I've gone beyond the stage of taking every failed item apart,but often there are fault codes like "Cyl 1 peak charge long" or "Topside switch failed pre injection".
The old RR Classic Lucas 4AS ecu's used to die of old age as another example,but the later 14CUX ones didnt seem to - I guess its just how they are made.The TD5 ones I have seen with oil inside them havent killed them,just caused missfires etc - but I guess bad examples would have fried completely.

Quick update:

Found two resistors on ECu board burned out - the blue smoke that makes all electronics work had escaped.

It's with Gary at TD5Alive, so he can look at the codes and, if necessary, clone it

There's an inherent design flaw (LR - surprise surprise) that means sometimes, the tracks on the PCB in the ECU might be handling 80 volts at 8 amps. What Richard-head thought that might be a good idea?
So, even if I found out why, and have to spend £500+ to replace it - all I have is a brand new, but badly designed piece of kit that I hope might last another ten years

Will update when I've found more about why such a vulnerable piece of overpriced kit should be so easily compromised within the normal operating conditions.