10 If adjustment to the mixture is required,
the tamperproof cap will need to be removed
from the carburettor to gain access to the
mixture screw. To do this, first unclip the fuel
trap from the side of the air cleaner unit, then
remove the air cleaner unit, ensuring that the
crankcase ventilation trap remains connected.
Prise free the tamperproof cap (with the aid of
a thin-bladed screwdriver), then with the
vacuum and emissions control pipes
connected to it, relocate the air cleaner unit
temporarily into position.
11 Turn the mixture adjustment screw
clockwise to weaken the mixture, or
anti-clockwise to richen it, until the CO
reading is as given in the Specifications. If a
CO meter is not being used, weaken the
mixture as described, then enrich the mixture
until the maximum engine speed is obtained,
consistent with even running.
12 If necessary, re-adjust the idle speed then
check the CO reading again. Repeat as
necessary until both the idle speed and CO
reading are correct.
13 Where required by law (as in some
European countries), fit a new tamperproof
cap to the mixture adjustment screw.
14 Disconnect the tachometer and the CO
meter, refit the air cleaner unit, and reconnect
the fan switch lead to complete.
Base idle speed and mixture
check and adjustment - 1.6 litre
EFi engines
15 Proceed as described above in
paragraphs 3 to 6 inclusive, then continue as
follows.
16 Run the engine at a fast idle speed until it
reaches its normal operating temperature and
the cooling fan cuts in. Check the CO content
of the exhaust, and compare it against the
specified reading. If the CO content reading is
incorrect, it can be adjusted by prising free
the tamperproof cap for access to the mixture
CO adjustment screw (see illustration), and
turning the screw in the required direction to
suit.
17 The operational idle speed is controlled by
the EEC IV engine management module and is
not adjustable. However, if the base idle
speed is incorrect, the module will not have an
accurate datum point from which to establish
the normal operational idle speed. If idle
problems have been experienced, the base
idle speed should be checked as follows.
18 Disconnect the multi-plug from the idle
speed control valve and increase the engine
speed to 2000 rpm, hold it at that speed for
30 seconds, then fully release the throttle and
check if the base idle speed registered is as
specified.
19 If adjustment is necessary, prise free the
tamperproof plug using a suitable small
screwdriver to gain access to the base idle
speed adjustment screw in the throttle body.
Turn the screw in the required direction to
adjust the base idle speed to the specified
amount. Turning the screw anti-clockwise
increases the idle speed (see illustration).
20 Increase the engine speed to 2000 rpm
again, hold it at that speed for 30 seconds,
then fully release the throttle once more.
Check and further adjust the base idle speed
if required, then fit a new tamperproof plug
into position.
21 Reconnect the idle speed control valve
multi-plug and check that the engine speed
briefly rises to about 900 rpm, then drops
down to the specified normal idle speed.
22 On completion, disconnect the
tachometer and the CO meter, but continue
running the engine at idle speed for a period
of about five minutes, to enable the engine
management module to relearn its values
before switching it off.
10 Steering, suspension and
roadwheel check
2
Front suspension and steering
check
1 Chock the rear wheels then jack up the
front of the car and support it on axle stands
(see “Jacking and Vehicle Support”).
2 Visually inspect the balljoint dust covers
and the steering gear gaiters for splits, chafing
or deterioration (see illustrations). Any wear
of these components will cause loss of
Every 10 000 miles or 12 months
1•15
9.9d Idle speed mixture adjusting
screw (A) and idle speed adjusting screw
(B) (Weber TLD carburettor)
9.9c Idle speed mixture adjusting
screw (A) and idle speed adjusting screw
(B) (Weber DFTM carburettor)
9.9b Idle speed adjusting screw (A) and
mixture adjusting screw (B) (Weber TLDM
carburettor)
10.2a Check the condition of the track rod
end balljoint dust cover (arrowed)
9.19 Base idle speed adjustment screw
(arrowed) on the 1.6 litre EFi engine
9.16 Adjusting the idle mixture CO content
on the 1.6 litre EFi engine
1
1595Ford Fiesta Remake