Mazda 121 - Poor Fuel Economy

TROUBLESHOOTING
GU'DE
F
26
POOR FUEL ECONOTIY
DESCalP-
fl0N
.
Fuel economy
unsatislaclory
ITRoUBLESHOOT|NG
H|NTSI
While luel consumption is drastically incfeased by city driving, shorl-run operalion,
slop and
go
driving, extended winler
warm-up
p€riods,
etc.,
as
opposed to
'trip"
mibage, an atlernpl should be
made to det€rmine th€se laclors wh€n con
fronted with
"poor
mileage condlrions. However, since the operator
is not
always at
taull, lhe iollowing is oJfercd.
O
Operator dep€sslng accelerator
more than usual due to
@
Air/Fuel rninur€ loo rich
low engine
power
.Hlgh
luel line
pl€ssure
.Poor
ignltion
@
Alcohol blended luel used
.Low
intake ai amount
@
High vehicle load
.Bake
dragsing
.Electronic
soark
advance conlrol svslem malJunclion
.Clutch
slipping/ATx slipping
.
Exhaust component restricted
NSPECTTON ACTION
1
Check
factors other than engine
.
Low
tire
pressufe
E7
page
O-2
.
Unrecommended lire size €
pag.
()-2
.
Clutch
slipping s
prge
H.-3
.
Brake
dragging
s
pege
P--5
.
Exhausl
cornponenl
restricred s
page
F-97
NO
2 Are air hoses connected corrcctly?
.7
page
F-Eil
NO
3 ls
'0O"
displayed on Self'Diagnosis Checker
with ignition swilch ON?
''
page
F-67
TEST SW: SELF TEST
Go lo next slep
NO
[alfunclion
Code No, dbplay€d
Ch€ck
lor
cause {Reter to soeclfied
check sequence)
G
gage
F-7o
"88"
ll.3he3
Check ECU t€rminal 1F voltage
F
page
F-114
Volage: Appror.
t2V
{lgnltlon
swltch
ON)
4
,t
OK, feplace ECU
t7
page
F-112
+
ll not
OK, check wiring
between
ECU
and Selt-Diagnosis Checker
ls lhere air leakage al intake air sl,stem com'
5 ls ai cleaner element clean?
r?
page
F-62
NO Beplace air cleaner elemer'1
6
Are ECU leminal voltages OK?
(Especially
2M, 2N, 2R and 2T)
.7
page
F-112
No Check
tor
cause
-
page
F-115
F-l17
F-l19
F-59