Air intake temperature sensor

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pogo001
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Joined: 07 Feb 2016, 12:42

Air intake temperature sensor

Post by pogo001 »

Hi.
I have a long term post running about starting issues with my 2008 Relay 2.2 hdi. The problem I have is that if starting from very cold, its not too bad. If I start the van from hot, it starts perfectly. But if I start from warm, even sitting in the sun warm, it starts immediately, but splutters and belches out white diesel smoke, until I drive and it warms up. I have changed each injector in turn, new fuel filter, fuel pressure regulator, but to no avail. I have cleaned the MAF sensor, and air pressure sensor. I have had diagnostics done which didnt give any faults.
So, it just occured to me, is there an air intake temperature sensor on this van? If so, where is it located? If its not reading the correct temperature, then I guess it will muck up the running of the van.
It has started to hunt occasionally on hot idle, although when I depress the clutch, it stops the hunting, and it runs fine, and has passed emissions tests not long ago.
Any help greatly appreciated.

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myglaren
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Re: Air intake temperature sensor

Post by myglaren »

Did you notice a little green 'bead' in the MAF?
That would be the thermistor for intake temperature.
Ruined MAF
Ruined MAF
On the right at 5 O'clock.

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white exec
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Re: Air intake temperature sensor

Post by white exec »

I guess there will be both an air intake temp sensor, and one for coolant temp.
Both usually affect the Injection ECU.

pogo001
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Re: Air intake temperature sensor

Post by pogo001 »

@Myglaren, no, but its pretty well covered, you cant see much iniside. I guess you are saying its part of the MAF sensor?

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myglaren
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Re: Air intake temperature sensor

Post by myglaren »

May not be in all MAFs - that one was mine, ruined by sucking in water and mud :(
In another thread there is a thermistor in the MAP and as Chris says, there is also the cooling system temperature that could be taken into account.

Amigoo33
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Re: Air intake temperature sensor

Post by Amigoo33 »

Isn't yours a hot film maf? My relay is 2011 and I just had a similar problem. If it is you can't really clean maf sensor but you probably cleaned an air temperature sensor. To diagnose if an air inlet temp sensor is sending correct info to computer use multimeter and find voltage between 1st and 2nd wire (if I remember correctly... measure 3rd and 4th too just in case). Write a voltage down and a outside temperature too so I could tell if your temp sensor is good(or if you have lexia you can find yourself or maybe google). At a certain temperature an air inlet temp sensor has to give a certain voltage and give correct info to a computer. Mine was showing like 100 Celsius when 15. Changed a maf fixed a problem. Worth a try.

Amigoo33
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Re: Air intake temperature sensor

Post by Amigoo33 »

Plus you changed injectors did you code them after? Did injector learning? Probably did but just to make sure. I changed my 2 and 4 places and it did not run properly.

wheeler
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Re: Air intake temperature sensor

Post by wheeler »

You really want to get the it on diagnostics live data just before you are about to start it from cold and see what the air inlet & coolant temp sensors are reading.

Amigoo33
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Re: Air intake temperature sensor

Post by Amigoo33 »

Or just do voltage and someone will help you here with a chart