JAGUAR X TYPE 2004 1.G MAF Sensor Cleaning Manual

X-Type Jaguar Information
Mass Air Flow (MAF) Sensor Cleaning – 08MY 2.2D (non-DPF)
Jaguar Part Number: C2S26978
MAF
This is a really important sensor; a properly functioning MAF makes a huge difference to the
performance of your engine.
Its function is to measure the quantity of air passing into the engine. This information is then fed
back to the ECU and determines the amount of fuel needed given the ambient conditions.
The device consists of a platinum hot wire that is kept at 200C. When air blows over it, the wire cools
and the ECU adjusts the fuelling, power and air intake to keep the wire at 200C. So the fuel provided
is proportional to the air flow.
When you stop the car the ECU heats the wire up very hot (300C) for a second or so to burn off any
dirt. Unfortunately over time some dirt can remain on the wire. This dirt build-up insulates the wire
and may result in false readings to the ECU. You can prolong the life of your MAF by gentle cleaning.
WARNING: DO NOT spray hard on the wires or scrape them with anything (not even a cotton bud) -
they are very delicate. A replacement MAF sensor will set you back around £80.
Why Bother?
Failure of mass air flow sensors is commonly misdiagnosed, and a replacement is expensive.
Mass air flow sensors can become contaminated with dust particles which affect the efficiency of
the sensor. These particles can be removed with solvents.
Before replacing the mass air flow sensor check for loose or broken wires and for air leaks in the
connecting air ducts and intake manifold. These leaks can cause similar symptoms to that of a
malfunctioning mass air flow sensor.
Failure symptoms
Bad or contaminated Mass Air Flow sensor can cause a wide range of vehicle drivability problems
such as stalling, especially when the engine is cold, misfiring, stuttering, poor acceleration, etc. and
often cause an engine fault light in the instrument panel to come on. There may be, but quite often
there will be no DTC code recorded.
Tools:
Torx Driver and bit to loosen MAF retaining screws
Electrical Contact Cleaner Spray
Clean rag or cloth
Skill Level:
Beginner
Time:
15 minutes
Dismantling:
To gain access to the MAF Sensor open the bonnet and remove the engine cover to expose the top
of the air intake and ducting in which the MAF sensor is located.

X-Type Jaguar Information
With the engine cover
removed you can see and
easily access the MAF sensor
in the middle of the engine
bay at the top of the air
ducts. (Arrowed)
Locate the MAF sensor on the large black
plastic pipe from the rear of the air filter
housing – it is rectangular and has a
wiring connector attached. There are two
retaining screws visible and accessible
from the top (Arrowed).
Top Tip: Check the connector carefully as
there have been reports of wires coming
adrift from the plug – it is possible to split
the plug open to restore the wires but
they are very short with little free play.
Remove the wiring connector to the MAFS by pressing down on
the lever to release the tang (Arrowed in picture above), and
carefully pull and jiggle the connector until free, set it aside
away from any danger of shorting.
Be careful not to pull or strain the wires as they are short and
there is not much room to manoeuvre.
Diesel MAF Sensor Wiring Sequence:
(looking from front of car toward windscreen)
White / GreenBrown / Blue Brown / Blue White / Blue

X-Type Jaguar Information
Remove the two torx screws securing the MAFS to the air duct
and store for re-use, be careful not to drop them into the engine
bay!
When removing the MAF, make sure you don't pull on the
wires, but gently hold the plug. Lift and pull the unit free from
the air pipe – underneath the rectangular top is a long plastic
tube that sits in the air flow of the pipe. Take care not to snag
either the tube or wire contacts it protects.
Examine the MAF Sensor and you should be able to see
two pairs of thin wires held in place in the MAFS tube.
Mine had a dull grey coating on the wires (hard to
photograph clearly).
Spray electrical contact cleaner on the wires in the tube through both the side and bottom
apertures. I used Maplin’s Electrical Cleaner Spray http://www.maplin.co.uk/electronic-solvent-
cleaner-30056 which evaporates away and does not leave any residue.
The grey powdery coating cleaned off leaving a shiny
surface after a few quick bursts of spray (again hard
to photograph but a definite change is noticeable)
Warning: *DO NOT* attempt to scrape or touch the wires with the spray tube or any other
instrument as they are VERY fragile and the sensor is an expensive piece of kit to replace. (£80+)
Re-Assembly:
First - Ensure the spray cleaner has fully dispersed and the MAF wires are dry, then just reverse the
procedure above:
Wipe the exterior casing and re-seat the sensor in its housing with the arrow pointing to the
rear of the car
Replace the 2 securing torx screws
Re-Connect the wiring to the MAF – (When you reconnect make sure that it really is firmly in
and that none of the wires are broken).
Replace the engine cover
Job done!