Jeep Cherokee 1999 Electronic Service Manual page 1194

X J
DESCRI PT I ON AN D OPERAT I ON (Cont inue d)
NOTE: Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
FUEL DELIVERY SYSTEM
Th e fu el deliver y syst em con sist s of:
• t h e fu el pu m p m odu le con t a in in g t h e elect r ic
fu el pu m p, fu el filt er /fu el pr essu r e r egu la t or, fu el
ga u ge sen din g u n it (fu el level sen sor ) a n d a sepa r a t e
fu el filt er loca t ed a t bot t om of pu m p m odu le
• fu el t u bes/lin es/h oses
• qu ick-con n ect fit t in gs
• fu el in ject or r a il
• fu el in ject or s
• fu el t a n k
• fu el t a n k filler /ven t t u be a ssem bly
• fu el t a n k filler t u be ca p
• a cceler a t or peda l
• t h r ot t le ca ble
F u el is r et u r n ed t h r ou gh t h e fu el pu m p m odu le
a n d ba ck in t o t h e fu el t a n k t h r ou gh t h e fu el filt er /
fu el pr essu r e r egu la t or. A sepa r a t e fu el r et u r n lin e
fr om t h e en gin e t o t h e t a n k is n ot u sed.
Th e fu el t a n k a ssem bly con sist s of: t h e fu el t a n k,
fu el pu m p m odu le a ssem bly, fu el pu m p m odu le lock-
n u t /ga sket , a n d r ollover va lve (r efer t o Gr ou p 25,
E m ission Con t r ol Syst em for r ollover va lve in for m a -
t ion ).
A fu el filler /ven t t u be a ssem bly u sin g a pr essu r e/
va cu u m fu el filler ca p is u sed. Th e fu el filler t u be
con t a in s a spr in g-loa ded fla p (door ) loca t ed below t h e
fu el fill ca p. Th e fla p is u sed a s a secon da r y wa y of
sea lin g t h e fu el t a n k if t h e fu el fill ca p h a s n ot been
pr oper ly t igh t en ed. Th e fla p is u sed a s pa r t of t h e
E VAP m on it or syst em wh en t h e veh icle is equ ipped
wit h a Lea k Det ect ion P u m p (LDP ). Th e fla p will be
in st a lled t o a ll fu el
equ ipped wit h LDP a n d E VAP m on it or syst em ).
Also t o be con sider ed pa r t of t h e fu el syst em is t h e
eva por a t ion con t r ol syst em . Th is is design ed t o
r edu ce t h e em ission of fu el va por s in t o t h e a t m o-
sph er e. Th e descr ipt ion a n d fu n ct ion of t h e E va por a -
t ive Con t r ol Syst em is fou n d in Gr ou p 25, E m ission
Con t r ol Syst em s.
Bot h fu el filt er s (a t bot t om of fu el pu m p m odu le
a n d wit h in fu el pr essu r e r egu la t or ) a r e design ed for
ext en ded ser vice. Th ey do n ot r equ ir e n or m a l sch ed-
u led m a in t en a n ce. F ilt er s sh ou ld on ly be r epla ced if
a dia gn ost ic pr ocedu r e in dica t es t o do so.
FUEL PUMP MODULE
Th e fu el pu m p m odu le is in st a lled in t h e t op of t h e
fu el t a n k (F ig. 1) or (F ig. 2). Th e fu el pu m p m odu le
con t a in s t h e followin g com pon en t s:
• A com bin a t ion fu el filt er /fu el pr essu r e r egu la t or
filler t u bes (equ ipped/n ot
• A sepa r a t e fu el pick-u p filt er (st r a in er )
• An elect r ic fu el pu m p
• A t h r ea ded lockn u t t o r et a in m odu le t o t a n k
• A ga sket bet ween t a n k fla n ge a n d m odu le
• F u el ga u ge sen din g u n it (fu el level sen sor )
• F u el su pply t u be (lin e) con n ect ion
Th e fu el ga u ge sen din g u n it , pick-u p filt er a n d fu el
filt er /fu el pr essu r e r egu la t or m a y be ser viced sepa -
r a t ely. If t h e elect r ica l fu el pu m p r equ ir es ser vice,
t h e en t ir e fu el pu m p m odu le m u st be r epla ced.
Fig. 1 Fuel Tank/Fuel Pump Module (Top View)
Fig. 2 Fuel Pump Module Components
FUEL PUMP
DESCRIPTION
Th e elect r ic fu el pu m p is loca t ed in side of t h e fu el
pu m p m odu le.
FUEL SYSTEM 14 - 3