sierrafery
Well-Known Member
For that one cleaning the MAP/IAT sensor is not enough cos it's IAT side is fubar, IMO you need a new one, the MAF might escape with a cleaning though if the fault persist you need a new one too
haggishunter
Member
ok so i have taken that air flow sensor piece off and the error remains the same - maybe that means its goosed?
haggishunter
Member
so i wonder if you can help me further - i reckon you are right - but dont know where the IAT is - also since my cheap OBD wont clear the errors i may just need the computer reset - any way of doing that mechanically like pulling a chip or something?
Thanks
Thanks
sierrafery
Well-Known Member
the IAT is part of the generically called "MAP sensor" that's why i said MAP/IAT and the IAT side used to fail more often on them, if a code reader can't clear fault codes means that the fault is present so you need new sensors to rule them out 100% and pray to not be a wiring issue
haggishunter
Member
or is there a way to check the MAF using a multimeter? Getting into advanced territory now....
haggishunter
Member
ahh ok got a crossover in responses there - ok so maybe a new one of those to start then....
haggishunter
Member
Strangely my code reader never clears errors - it says the car must be siwtched off with the ignition on and then when i hit CLear it doesn't clear them. Well.... it says it doesnt anyway but it seems to have cleared the first error and wont clear these - like you say maybe these are current and permanent
sierrafery
Well-Known Member
You can't rule it out 100% with nultimeter unless you get open circuit then you know it's fubar for good, no certain way to check a MAF with multimeter, with a scanner on live inputs eventually if you know the correct reading range for it
Yes, that's what it means and no diag tool would clear permanent codes
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haggishunter
Member
aww crap its like 260 quid for a new one - and EuroCar parts actually have it in stock. would be just my luck if i got a new one and it wasnt the problem :-( or the problem didnt resolve it self or the computer wouldnt clear or something. Whatever could go wrong - for me - ill defo go wrong ....
sierrafery
Well-Known Member
Unfortunately the boost and air flow sensors are not made to last forever, about 5-6 years is theyrs life span these days especially on supercharged "small" engines
Thks for the update
Indeed really need a far better scanner , there’s a gap iid tool which are around £450 , other basic one which is quite popular is the Autel ap200 which is around £80 , but have to ensure u get the correct one that’s has all the service software installed as there’s different ones of the ap200
At a minimum need a scanner that will do a DPF reset
Wondering if u have a vacuum or intercooler leak, know when I had problems with my D3 I carried out a smoke test and found several air leaks but urs is a totally different engine
Alas I suppose the options u have is buy a far better scanner, or find a decent independent garage otherwise u could be chasing this error for eternity
Another thing u mentioned was regards to it being very sooty and garage in the past has simply reset the DPF therefore would it be worth finding a garage that does proper DPF / AD blue injector cleaning to first ensure that everything is clean and the engine isn’t being restricted in any way
Someone far more knowledgeable than myself will be able to help u further
Sorry that’s not much help
Indeed really need a far better scanner , there’s a gap iid tool which are around £450 , other basic one which is quite popular is the Autel ap200 which is around £80 , but have to ensure u get the correct one that’s has all the service software installed as there’s different ones of the ap200
At a minimum need a scanner that will do a DPF reset
Wondering if u have a vacuum or intercooler leak, know when I had problems with my D3 I carried out a smoke test and found several air leaks but urs is a totally different engine
Alas I suppose the options u have is buy a far better scanner, or find a decent independent garage otherwise u could be chasing this error for eternity
Another thing u mentioned was regards to it being very sooty and garage in the past has simply reset the DPF therefore would it be worth finding a garage that does proper DPF / AD blue injector cleaning to first ensure that everything is clean and the engine isn’t being restricted in any way
Someone far more knowledgeable than myself will be able to help u further
Sorry that’s not much help
Hi mate
Are u able to unplug either the MAP / MAF sensor on these plse or is that only for older engines as a way of eliminating a faulty sensor where it reverts to the basic software ECM settings
Weird where the garage use to just reset the DPF and seeing the OP mainly done town driving if the DPF/ Adblue injector is blocked up and not been cleaned out properly and in turn possibly suffocating the engine ??
Trying to remember if it was the Maf sensor that also reads the external air temperature so if there faulty show a wrong temperature readout on the instrument panel , plus always thought that provided a temperature signal to a FBH for when to come on , as always might be completely wrong, lol
Of course know ur more knowledgeable than myself but just a guess
Many thks as always
Agree totally. many cleaners leave a deposit which you really flipping don't need on a MAP etc.
Shops do sell "sensor cleaner" so that should be used.
Obvs!!
sierrafery
Well-Known Member
Hi, unplugging the MAF works for almost all diesel vehicles to rule the sensor out as the default keeps the engine running at around 90% performance so usually better than with a faulty MAF which gives erratic readings connected, not the case for MAP/IAT which once unplugged goes to a default with low power just to keep you moving
haggishunter
Member
Hi sorry no if i unplug the MAF it just does the same thing - on startup i get about 5 seconds where i can rev the car fully up past 50000 RPM and then i get a Restricted Performance error and then it wont rev above 3100 RPM and gets there slower too. No change in with the MAF connected or not. I have now reset the errors and there are none. i have disconnected the battery for 30 mins then put it all back together. no errors but still now getting restricted performance. Took it for a spin, it runs OK but ony up to 3100 RPM and slow getting there and its sluggish. But always the Red Exclamation and Restricted Performance.
Having a look at your thread, you've said that the dpf is an issue. If it is blocked then a maf will be logged as well as air won't pass through it because it can't leave the engine!
Do you have any diagnostic equipment?
If not you could be starting a parts cannon ..
I've just dealt with a BMW X1. Complete blocked dpf with maf errors to boot.
The live data will show dpf pressure reading and maf readings and then you can go from there.
The maf can get dusty and the map gets oily due to the mixture of exhaust dust from the egr and the oil film being supplied from the engine breather...
Do you have any diagnostic equipment?
If not you could be starting a parts cannon ..
I've just dealt with a BMW X1. Complete blocked dpf with maf errors to boot.
The live data will show dpf pressure reading and maf readings and then you can go from there.
The maf can get dusty and the map gets oily due to the mixture of exhaust dust from the egr and the oil film being supplied from the engine breather...
sierrafery
Well-Known Member
That can happen in case if the "main" fault is with the MAP/IAT sensor not with the MAF so replace the MAP first then if it runs better you can check with the MAF... to rule out the MAF by unplugging it works only if a faulty MAF is the main cause of the malfunction and all the rest is OK, then if you unplug it the engine would run better but as your's has a IAT fault too this kind of diagnose doesnt work.... maybe you should plug in a more reliable scanner cos once you get a performance error message on the display there should be a fault code logged too in the ECU cos these are related if you see what i mean
Not always the case unplugging the maf, the modern Opel/Nissan/Renault engines can stop running if the maf is messed with ..
sierrafery
Well-Known Member
Hi, that's why i saidNot always the case unplugging the maf, the modern Opel/Nissan/Renault engines can stop running if the maf is messed with ..
as about your statement about modern Opel/Nissan/Renault engines i can't contradict you... just confirm you speak about diesels cos the petrol engines are a completely different story also on some modern diesels there are MAF/IAT or MAF/AAP sensors not simple MAF sensor which delivers only air flow reading, the unplugging trick doesnt work for these.
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haggishunter
Member
i think it makes sense that the MAF/IAT has failed as it does the same thing and perfromsm the same whether its plugged in or not. Also i like your idea about still replacing the MAP first in case its damaged. Which makes me also think - can i troubleshoot the MAP or diagnose it with my meter. i suppose first thing i should do is disconnect that and see if it starts or does the same thing or logs errors etc. i will unplug it now and see if it even starts.
