Cleaning mass Airflow Sensor

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My Name: samuelodog

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Hi - Any advice on how to do this?

I believe the sensor is a bit of electrical kit somewhere inside the MAF, I have the cleaning spray, but I don't know how to get to the sensor.

I can't even seem to be able to take out the MAF - there is a large black rubber pipe attached to it using some kind of metal clip that I can't seem to get off. The other end is screws, which is fine.

Anybody done this before?

Thanks
My Name: samuelodog

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Hi

I think I know the problem.

There is a clamp fixing the Air intake hose to the MAF. This clamp appears to
be a crimped single use clamp. There is no slot for a screwdriver or any tool to get into to
loosen the darn thing.

Anyone taken one of these off before?

Can I get replacements if I break it?

Should I just abort this mission to clean the MAF and take it in?

Thanks
My Name: Missing Lincs

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Model: C3 2002-2005, Original shape model
Year: 2004 (04)
Engine Size: 1.1
Fuel Type: Petrol
Trim Level: Desire
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DPF: No
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I've never taken the sensor off on a C3 so I don't have any specifics for you but if it helps:-

All the ones I've worked on with other makes have been either Bosch. Delphi or Denso, and in all the cases I've come across you can remove the sensor from the housing. Usually a couple of screws somewhere in the area where the connector and wiring attaches.

You used to be able to get new sensors however, all the ones I've seen recently have been non-genuine pattern parts which from what I've seen on other forums don't get good reports. Genuine replacements now only come as the complete assembly.

Even if you get the housing off, chances are you won't be able to clean the sensor if it doesn't come out of the housing. Like I say, no specifics here for C3s as I've never tried but has always been the case on the ones I've tried.

The housings are always a very good fit and a struggle to get off without damaging, but you must make sure you don't damage any seals. Any air getting into the system after the sensor will affect the airflow to the engine and won't be known about by the engine management. Go carefully even if it does feel like you need a big hammer and a flat-bladed screwdriver.

If you do get to the sensor then cleaning is fairly easy, its just a wire with resistance. As air flows over the wire, the temperature changes and therefore so does the resistance, this is picked up by the engine ECU. Over time the sensor can oxidise which will insulate it slightly and cause an incorrect reading, it may also have some build-up of other rubbish, despite being protected by a filter which we all meticulously change ever year.
If at first you don't succeed, destroy all the evidence and pretend you never tried :lol:
My Name: Missing Lincs

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Posts: 844
Joined: Mon Mar 05, 2012 9:29 pm
Model: C3 2002-2005, Original shape model
Year: 2004 (04)
Engine Size: 1.1
Fuel Type: Petrol
Trim Level: Desire
Gearbox: Manual 5 speed
DPF: No
LHD or RHD: RHD (UK)
Engine name: TU3 (75 PS)
Location: United Kingdom
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Almost forget. If the clamp you have is the 'crimp' type, they are not re-usable. They are easy to get hold of from motor factors or you could use a different type of clamp with a screw adjustment. If you go for the 'crimp' type don't use pliers to try to tighten it, either a tool made for the job or a pair of pincers with the jaws blunted.
If at first you don't succeed, destroy all the evidence and pretend you never tried :lol:
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My Name: Arfur Dent

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Model: C3 2002-2005, Original shape model
Year: 2002 (52)
Engine Size: 1.4 (16v)
Fuel Type: Diesel
Mileage: 100000
Trim Level: Exclusive
Gearbox: Manual 5 speed
DPF: No
LHD or RHD: RHD (UK)
Engine name: DV4 16-valve diesel (90 PS)
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There is some info for the 16v diesel, it may give you some ideas

https://citroenc3owners.com/diesel-c3-ti ... i-t80.html

Image
The MAF is in this bunch of plastics, its held on by a jubilee clip and some torx bolts. If you have to cut the factory clip off, do as missing lincs says and use a Jubilee Clip of the correct size.

If you need a new one, you can get a new MAF at Euro Car Parts



Citroen C3 MAF
Citroen C3 MAF
C3 HDi MAF
C3 HDi MAF
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My Name: samuelodog

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Hi,

I have decided to give up on the cleaning Air Flow Sensor track.
Apparently, you can't build out and get to the actual sensor!

So I bought sensor cleaner for nothing!

But.. I think I should have a crack at replacing the whole MAF myself.

My garage said this will cost £130.

But I see on ebay - you can pick up a MAF for £30, with 12 month guarantee:

https://www.ebay.co.uk/itm/Air-flow-mass ... 0375553096

Anyone had any experience of these parts? Would the ebay one suffice?


Thanks
My Name: Missing Lincs

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Model: C3 2002-2005, Original shape model
Year: 2004 (04)
Engine Size: 1.1
Fuel Type: Petrol
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DPF: No
LHD or RHD: RHD (UK)
Engine name: TU3 (75 PS)
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My experience of unbranded replacements has not been good, they have just about lasted the guarantee period out.

I've done a few of these recently and go for an OEM part direct from a specialist supplier rather than through a car dealership. There should be a manufacturers name and part number on the one currently in your car. Changing isn't difficult. The only thing I was once warned of by a garage is that they need calibrating, well so far I have yet to come across one that does.

Go for it!
If at first you don't succeed, destroy all the evidence and pretend you never tried :lol:
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My Name: Arfur Dent

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Model: C3 2002-2005, Original shape model
Year: 2002 (52)
Engine Size: 1.4 (16v)
Fuel Type: Diesel
Mileage: 100000
Trim Level: Exclusive
Gearbox: Manual 5 speed
DPF: No
LHD or RHD: RHD (UK)
Engine name: DV4 16-valve diesel (90 PS)
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samuelodog wrote:Anyone had any experience of these parts? Would the ebay one suffice?
Have a look at my post https://citroenc3owners.com/diesel-c3-ti ... -t802.html, it covers a very similar question to yours. I ended up getting the cheap ebay unbranded MAF and its been in a few weeks and has been working very well. But as Missing Lincs points out, quite how long its going to last is a question and still unknown.


I have decided to give up on the cleaning Air Flow Sensor track.
Apparently, you can't build out and get to the actual sensor!
You can get to the sensor on the MAF fitted to the 16v 1.4 diesel, use the extension tube on the MF cleaner with the MAF off the car. I didn't think the 8v was so different.
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My Name: samuelodog

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ah -

so (I haven't yet removed the MAF because I still need to get clips) presumably the sensor will be some kind of wiring dangling down into the pipe of the MAF?
So I just spray this with the cleaner?

I can't seem to find anything anywhere about the specifics of this operation.

I can't even find a picture of what the inside looks like to see if it's possible.
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My Name: C3driver52

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Fuel Type: Petrol
Mileage: 79984
Trim Level: VTR+
Gearbox: Manual 5 speed
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Engine name: TU3 (75 PS)
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I can't even find a picture of what the inside looks like to see if it's possible.
Ah, pictures!

Try these:
(The are from the 1.4 16v Diesel, it has a narrower, more oval body, but the 8v 1.4 has a larger, round body giving you more room to see what you are doing.
Citroen C3 Diesel MAF cleaning and internal components
Citroen C3 Diesel MAF cleaning and internal components
The red arrow shows the location of the air flow sensor, its inside the slot (it is the slot).

The white arrow points to the air temperature sensor, it looks like a thermistor.

Citroen C3 MAF cleaning
Citroen C3 MAF cleaning
This shows the air flow sensor slot a bit more clearly. One of the large faces inside the slot is the airflow sensor.


The cleaning product, like this one on Amazon is a solvent based cleaner which doesn't damage the delicate parts of the MAF. To effectively clean the MAF, spray the solvent over both the thermistor and flow sensor (red arrow and white arrow). The solvent action will clean off any containments that are on the sensors that could be causing a weak or non-existent signal.
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