Defender91

Defender91

Active Member
Hi,
I've been advised that if you unplug the MAF sensor the ECU goes into a preset assumed mode. If that's the case, would it render my remap useless?
Thanks for replies in advance.
 
Defender91 said:
Hi,
I've been advised that if you unplug the MAF sensor the ECU goes into a preset assumed mode. If that's the case, would it render my remap useless?
Thanks for replies in advance.
Click to expand...
According to your profile your's is from 2001 so Eu2 engine which means that the MAF is only for EGR management which i doubt it's subject of the remap. If the EGR is bypassed the MAF is no factor
 
Hi, thanks for the responses.
Yes, the disco is is 2001, it supposedly had a stage 1 remap by empire according to the bloke I bought it off, and he seemed genuine. Thing is , I have never driven any other TD5 to compare it to, but I towed the car trailer yesterday for the first time and it did seem quite underpowered as to what I'd expect.
I know the MAF sensor is knackered by the hawkeye, but there's no obvious difference with it plugged in or not.
It's still got the EGR, everything is completely stock on it to my knowledge apart from the supposed remap and wastegate tweaking they did at the time.
Might be worth noting there's a bit of smoke under heavy load.
Thanks
 
Defender91 said:
It's still got the EGR,
Click to expand...
Then first of all check your MAP sensor cos it's probably full of gunk, clean it with carb cleaner spray as the little hole in it's bottom near the probe to be clear, eventually clean up the EGR valve too... then if you have hawkeye go for a ride with it plugged for live data and watch the manifold absolute pressure reading under load, it should go up to 230 KPa or there is a boost leak or other issue
 
Ok, I cleaned the egr and map sensor a few months ago, I've just checked the Map again and it was slightly oily but the little hole was still clear.
Will see what the hawkeye says when I take it out tonight and'll report back.
Thanks



sierrafery said:
Then first of all check your MAP sensor cos it's probably full of gunk, clean it with carb cleaner spray as the little hole in it's bottom near the probe to be clear, eventually clean up the EGR valve too... then if you have hawkeye go for a ride with it plugged for live data and watch the manifold absolute pressure reading under load, it should go up to 230 KPa or there is a boost leak or other issue
Click to expand...
 

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After taking it out, it breifly hit 236 kpa uphill and quite regularly sat at 210 odd when accelerating.
sierrafery said:
Then first of all check your MAP sensor cos it's probably full of gunk, clean it with carb cleaner spray as the little hole in it's bottom near the probe to be clear, eventually clean up the EGR valve too... then if you have hawkeye go for a ride with it plugged for live data and watch the manifold absolute pressure reading under load, it should go up to 230 KPa or there is a boost leak or other issue[/QUOT
Click to expand...
 
255/55/R18 Goodyear all terrians.
Mabye I'm making a fuss of nothing, but the car and car trailer was less than a tonne , and some of the slower steeper hills still needed 1st or 2nd to get up. Id say the power is similar to my old 200tdi.
 
Don't reckon so, the revs don't increase without the speed going up, going through the receipts for it it had clutch about 50,000 miles ago.
Is the smoke under load an indication? Is not thick but it's enough to make the cars behind back off:D
 
Black smoke at that boost means overfuelling as at 210 - 236 kPa i doubt that's a boost leak... something is wrong with the management IMO as the tyres are standard too... it's possible that the frigging EGR to make tricks, unplug the electrical connector of the EGR solenoid and see how it goes then... you said you checked the MAP sensor but did you check the EGR valve too to not be gunked up?...also the air filter is new enough?
 
I cleaned the egr out when I did the MAP, it initially had a historic code that the egr was stuck but I tested it with a vaccum gauge and moved fine after cleaning it.
I've just found a reciept to the previous owner for an ' Engine ECU' from a 4x4 breakers yard for £200 quid. I take it it's not standard practice to fit another ECU when getting it mapped? Is there any way to tell if it has been mapped with my Hawkeye?
I'll try unplugging that and get back to you, it had an air filter about 6000 miles ago.
Thanks
 
What's the ECU's serial(part) number on it's side? IIRC hawkeye does not show you that unless if it's displayed while you connect it to the menu like for the SLABS, i forgot since i used mine
 
Not sure which number you mean, so here's pics of all the numbers on it.
I did notice that the SALL number doesn't match the cars chassis number.
 

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Defender91 said:
Not sure which number you mean, so here's pics of all the numbers on it.
I did notice that the SALL number doesn't match the cars chassis number.
Click to expand...
Now you have the answer, that NNN500250 ECU is for Eu3 engines and according to the VIN(...4A843708) was removed from a late 2004 facelift and it's the only NNN ECU which doesnt accept Eu2 fuel maps(unless the remappers invented something since) so that's why you have black smoke cos the Eu2 injectors are working with different pressures also the AAP sensor is with 3 wires instead of 4 like the Eu3 engine has so the ECU is missing the ambient air temp input which is used for smoke limiter map and fuelling calculations and the injector codes are wrong as well. Not good, your engine might get hurt by high EGTs and it's definitely not fuelled well unless you have a EGT gauge to confirm it's normal. Better buy a MSB ECU or NNN000120 or 500020 remapped for Eu2 and sell this one cos it can be valuable for somebody with a facelift
 
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Ah. Its amazing how often a curious interest into a minor problem turns out to be something far bigger(and more expensive).:D
Thanks so much for your help on this, there is no way I would have clocked onto it having the wrong ECU, would have started looking elsewhere and spending money unnecessarily.
I'll start looking for another ECU, is it a bit too much of a gamble to get one from a breakers? Or is it better to just pay more and get a reputable one, do they go wrong?
Thanks
sierrafery said:
Now you have the answer, that NNN500250 ECU is for Eu3 engines and according to the VIN(...4A843708) was removed from a late 2004 facelift and it's the only NNN ECU which doesnt accept Eu2 fuel maps(unless the remappers invented something since) so that's why you have black smoke cos the Eu2 injectors are working with different pressures also the AAP sensor is with 3 wires instead of 4 like the Eu3 engine has so the ECU is missing the ambient air temp input which is used for smoke limiter map and fuelling calculations and the injector codes are wrong as well. Not good, your engine might get hurt by high EGTs and it's definitely not fuelled well unless you have a EGT gauge to confirm it's normal. Better buy a MSB ECU or NNN000120 or 500020 remapped for Eu2 and sell this one cos it can be valuable for somebody with a facelift
Click to expand...
 
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