Low Rev Throttle Response, at a loss now!

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I had just noticed that the previous owner had bared the 'Black' wire going onto the ECU (red connector) and I am concerned that they were up to something there - no idea what they were doing or hoping for - any ideas? Its intact though - looks like they may have been trying to bypass something???
 
Well, if it's just stripped back it should still be doing its job.

The fact that it's the black one is interesting. That's earth, and apparently there are four earth pins in the black connector. I don't know if there are four black wires matching those, but I see two on some diagrams. How many do you have, and are they all stripped?

Bearing in mind that I guessed bad earth I can't help wondering if someone else thought the same and was trying to improve it.

Also apparently, one black should go to an earth point in the seat box, and be joined there by a black coming from the OBD socket. The other goes to the EGR modulator.

I don't think this is much help in diagnosing but does possibly show that this has been an ongoing problem.
 
I had similar issue to this. I changed injector harness and all bits you have. Mine would feel like it hit fuel cut and would hesitate or kangaroo.
Eventually, it died on the m4 in the rain. No one could work it out. I rewired the throttle inside the cab and it was cured. For the sake of what this costs to do id do it if you can’t work out what’s wrong. It’ll then future proof it anyway. If i ever bought another td5 defender it would be first thing I did. Crispy crappy loom around gearbox tunnel etc.
 
boguing said:
Well, if it's just stripped back it should still be doing its job.

The fact that it's the black one is interesting. That's earth, and apparently there are four earth pins in the black connector. I don't know if there are four black wires matching those, but I see two on some diagrams. How many do you have, and are they all stripped?

Bearing in mind that I guessed bad earth I can't help wondering if someone else thought the same and was trying to improve it.

Also apparently, one black should go to an earth point in the seat box, and be joined there by a black coming from the OBD socket. The other goes to the EGR modulator.

I don't think this is much help in diagnosing but does possibly show that this has been an ongoing problem.
Click to expand...

Just the one into that connector and its the same gauge as the earthed one to the chassis underneath the ECU. Its worrying though.....what were they up to???
 
tweedandbriar said:
Just the one into that connector and its the same gauge as the earthed one to the chassis underneath the ECU. Its worrying though.....what were they up to???
Click to expand...
I think it might be worth cleaning up that earth point, but if it looks ok when it's apart, it's probably ok.

Failing that I'm afraid I'd break my own rule and follow @resto_d1's plan.
 
boguing said:
I think it might be worth cleaning up that earth point, but if it looks ok when it's apart, it's probably ok.

Failing that I'm afraid I'd break my own rule and follow @resto_d1's plan.
Click to expand...

Thats - yeah, I am thinking of replacing the wiring loom from the throttle to the ECU.... another fooking £60, not much, but it all adds up eh!
 
Scrub what I just wrote. Try the loom. Because it was touching 6v I don't think the pedal potentiometer is the culprit.
 
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Evening!

Earlier, I hooked up the Nanocom and saw that the throttle was set to a 3 track. So far as I know my 1999 110 (10p) is a 2 track pedal. I reset it to 2 track. I've not gone any further than back from my local after a pint or two of Tribute (Cornish best!!), so can't really report back as yet, it's only a half a mile drive. What dya think, would this make much difference?
 
It shouldn't make any difference.

If it did then either track 3 is damaged (which I doubt - because it jumps to 6v when it's only supplied with 5) or the wire for track 3 is damaged, which again I doubt because of the 6v.

Go for a longer drive!
 
boguing said:
It shouldn't make any difference.

If it did then either track 3 is damaged (which I doubt - because it jumps to 6v when it's only supplied with 5) or the wire for track 3 is damaged, which again I doubt because of the 6v.

Go for a longer drive!
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I'll find a pub a bit further away then, yeah? 😁
 
Well, that was a different drive!! Not 100% but definitely easier and almost no jumping! All I did was change from 3 track to 2 track via the Nanocom. The only thing was, little or no boost at all in low revs and low speed in a higher gear, necessitating changing down again and upping the revs. I guess I might need to revisit the boost now, maybe put the wastegate back to 14 threads and start over. I have a throttle pedal overlay coming so will fit that too. I also have a standard chip for the ECU coming, it will 'click' in as Empire Tuning fitted the small cage for them to clip into. All things being equal I feel its getting a little closer to being resolved.
 
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Certainly, going back to standard is the best place to start.

Why's it better with two tracks? Points to a dodgy track 3 or its wire to the ECU, and supported by its trace via Nanocom. But how can it put out more than 5v? Why did the MAF also look wrong?

Have you got the log of the last drive - to see if the MAF error is still there?
 
boguing said:
Certainly, going back to standard is the best place to start.

Why's it better with two tracks? Points to a dodgy track 3 or its wire to the ECU, and supported by its trace via Nanocom. But how can it put out more than 5v? Why did the MAF also look wrong?

Have you got the log of the last drive - to see if the MAF error is still there?
Click to expand...

Taking it out later this afternoon...will put up the log then - cheers!
 
Here's this evening's Nano log... It seems changing from 3 track to 2 track hasn't done anything really - I assume as its reading 3 tracks there's a 3 track pedal installed(?)

Still surging (but less) and less 'hopping'...getting there, I think. The throttle pedal overlay turned up so that will be going on either tomorrow or Saturday.

Nano_04_07_24
 
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