Jeep Cherokee 1999 Electronic Service Manual page 1229

14 - 38 FUEL SYSTEM
DI AGN OSI S AN D T EST I N G (Cont inue d)
Fig. 22 Sensor Locations—4.0L Engine
Fig. 23 Rubber L-Shaped Fitting—MAP Sensor-to-
Throttle Body
(20) Ra ise a n d su ppor t veh icle.
(21) Ver ify bot h oxygen sen sor wir e con n ect or s a r e
fir m ly con n ect ed t o sen sor s. In spect sen sor s a n d con -
n ect or s for da m a ge (F ig. 25).
(22) In spect for pin ch ed or lea kin g fu el t u bes.
In spect for pin ch ed, cr a cked or lea kin g fu el h oses.
(23) In spect for exh a u st syst em r est r ict ion s su ch
a s pin ch ed exh a u st pipes, colla psed m u ffler or
plu gged ca t a lyt ic con ver t or.
(24) If equ ipped wit h a u t om a t ic t r a n sm ission , ver-
ify elect r ica l h a r n ess is fir m ly con n ect ed t o pa r k/n eu -
t r a l swit ch . Refer t o Au t om a t ic Tr a n sm ission sect ion
of Gr ou p 21.
(25) Ver ify elect r ica l h a r n ess con n ect or is fir m ly
con n ect ed t o veh icle speed sen sor (F ig. 26) or (F ig.
27).
Fig. 24 Engine Coolant Temperature Sensor—
Fig. 25 Location of Oxygen Sensors
(26) 2.5L 4–Cylin der E n gin e On ly: Ver ify good
elect r ica l con n ect ion a t power st eer in g pr essu r e
swit ch (F ig. 28). Th is swit ch is n ot u sed wit h 4.0L
en gin es.
(27) Ver ify good elect r ica l con n ect ion s a t fu el pu m p
m odu le con n ect or a t fr on t of fu el t a n k (F ig. 29).
(28) Ver ify good E VAP ca n ist er ven t lin e con n ec-
t ion a t fr on t of fu el t a n k (F ig. 29).
(29) Ver ify good fu el su pply lin e con n ect ion a t
fr on t of fu el t a n k (F ig. 29).
(30) In spect a ll fu el lin es/h oses for cr a cks or lea ks.
(31) In spect t r a n sm ission t or qu e con ver t or h ou sin g
(a u t om a t ic t r a n sm ission ) or clu t ch h ou sin g (m a n u a l
t r a n sm ission ) for da m a ge t o t im in g r in g on dr ive
pla t e/flywh eel.
(32) Ver ify ba t t er y ca ble a n d solen oid feed wir e
con n ect ion s t o st a r t er solen oid a r e t igh t a n d clea n .
In spect for ch a ffed wir es or wir es r u bbin g u p a ga in st
ot h er com pon en t s.
Typical
X J