tom1979

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Full Member
So today I was driving to the Peterborough show ground, on the A1 doing about 80mph in my td5 defender and suddenly loss of power, bit of black smoke. So I eased off the power anticipating where to stop and it seemed fine after. On the way home it did it again but this time no black smoke (that I noticed).

I've searched the forum and it seems quite common for this to happen with an increase in engine temperature but neither time I noticed anything odd with the temp. I've got no fault codes either so wondering what it might be. Revving the engine (right up) stood still it's fine, just seems to be when it's under load.
 
Did you get the engine management light coming on? Mine did this a couple of times back in 2013 when it went into limp mode on the motorway. I was also seeing a 'high speed crank error' on the Nanocom, though not on the occasions when it did this. The Nanocom also showed some wild cylinder balance values when the engine was running. The solution was a new OEM/genuine crank position sensor, rather than the Britpart one that was installed, and it's not done it again. I'm not saying that yours is the same, but it could be worth considering.
 
No lights nothing! Even looked at cylinder balance and all was normal. Literally a momentary loss of power a puff of black smoke and back to normal
 
So I took it for a spin today with the Lynx plugged in and recording. Bit of a waste of time because when you're watching it back you can't hear the engine! Anyway I have managed to reliably replicate the problem but getting it up to about 3500 revs at which point the power dies a bit. After this it was dying a bit at around 2700 revs. I am wondering if there is a hose collapsing or something? Not sure how I can check without rigging up cameras in the engine bay.
The problem does not exist at a standstill, only when driving and under some load (slight hill etc)
 
try it with the maf disconected

Do you reckon it'll make a difference? Seems ok until it gets to a point. I've had a dead maf before and it was running rough all the time. Also the air flow voltage does change. Worth a go though!
 
I had a heavily mapped td5 that had a misfire approx 3000rpm as the maf had maxed out at around 650.
As a temp measure I unplugged maf then ordered a maf clamp from Bell Auto's that fixed the issue along with a boost box. Some on here will say it's the wrong way of doing it but it worked for me, and is recommended by a few td5 tuners.
 
Do you reckon it'll make a difference? Seems ok until it gets to a point. I've had a dead maf before and it was running rough all the time. Also the air flow voltage does change. Worth a go though!
Air flow at idle should be 50-60
 
I had a heavily mapped td5 that had a misfire approx 3000rpm as the maf had maxed out at around 650.
As a temp measure I unplugged maf then ordered a maf clamp from Bell Auto's that fixed the issue along with a boost box. Some on here will say it's the wrong way of doing it but it worked for me, and is recommended by a few td5 tuners.

Cheers my "boost box" is built in the more I look at the data the maf readings are all over the place I'm hoping this'll be a cheap (£100) fix ! What's a MAF clamp? Also did you get any fault codes with yours?
 
Maf clamp is an electrical box that connects to the wiring on the maf. It alters signal sent to the ecu to stop it cutting fuel
 
No codes, but the guy doing my map predicted it would happen as I had a very aggressive tune installed so when it happened I knew what to do and all was good afterwards
 
No codes, but the guy doing my map predicted it would happen as I had a very aggressive tune installed so when it happened I knew what to do and all was good afterwards
Cheers that's great news. I've got a switchable ecu, one is fast economy about 150-160, the other is apparently around 195+
 
May have found the problem, driving up the road with the bonnet off I could see the intake pipe collapsing!

 
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air flow at idle is 4.4kg/hr I did read somewhere what it was meant to be and it was a lot higher than this. Do you know roughly what it should be
That's clear sign of dead MAF ...that collapsing thing can be caused by a restriction on the intake before that pipe
 
It's got a snorkel fitted which I have undone for now which seems to have helped.
 
Put a new air filter too then, eventually go for a short test drive with filter removed... and unplug the MAF cos it's fubar and the engine might run better on open circuit default, especially if it's Eu3 engine
 
I replaced the MAF, it certainly pulls away smoother now. Air filter (genuine) is probably only 500 miles old.
 

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