Chrysler RAM TRUCK 2500 1994 Service Manual page 730

• ENGINES 9 - 9
S E R V I C E DIAGNOSIS (DIESEL ENGINE) - PERFORMANCE (CONT.)
CONDITION POSSIBLE CAUSES COMMOTION
ENGINE H A R D TO
START, OR WILL
N O T START—SMOKE
FROM EXHAUST
( C o n t ' d )
Fuel list pump Inoperative.
I n j e c t i o n p u m p t h r o t t l e l i n k a g e
l o o s e o r d a m a g e d .
C o n t a m i n a t e d f u e l .
Fuel screen plugged.
One or more injectors worn or not
operating properly.
Worn or inoperative injection pump.
Injection p u m p o u t o f t i m e .
V a l v e s i n c o r r e c t l y a d j u s t e d .
Engine compression low.
Measure lift pump outlet pressure. If needed repair or replace pump.
V i s u a l l y c h e c k t h e l i n k a g e . T i g h t e n / r e p l a c e l i n k a g e .
V e r i f y b y o p e r a t i n g t h e e n g i n e w i t h c l e a n f u e l f r o m a
t e m p o r a r y t a n k . C h e c k f o r p r e s e n c e o f g a s o l i n e . D r a i n a n d
f l u s h f u e l s u p p l y t a n k s . R e p l a c e f u e l / w a t e r s e p a r a t o r f i l t e r .
Check fuel screen.
Check/replace bad improperly operating injectors.
Visually check fuel delivery with an externally connected injector to one of
the pump outlets. Repair or replace the pump if fuel is not being delivered.
C h e c k / t i m e t h e p u m p ( r e f e r t o G r o u p 14, F u e l S y s t e m ) .
A d j u s t v a l v e s .
Check compression to identify the problem.
E N G I N E STARTS,
BUT WILL N O T
KEEP R U N N I N G
Idle s p e e d t o o l o w f o r t h e
a c c e s s o r i e s .
I n t a k e a i r o r e x h a u s t s y s t e m
r e s t r i c t e d .
A i r i n t h e f u e l s y s t e m o r t h e
f u e l s u p p l y is i n a d e q u a t e .
Fuel w a x i n g d u e t o e x t r e m e l y
c o l d w e a t h e r .
C o n t a m i n a t e d f u e l .
A d j u s t t h e i d l e s p e e d .
V i s u a l l y c h e c k f o r e x h a u s t r e s t r i c t i o n a n d i n s p e c t t h e a i r i n t a k e .
R e p a i r / r e p l a c e r e s t r i c t i n g p a r t s .
C h e c k t h e f l o w t h r o u g h t h e f i l t e r a n d b l e e d t h e s y s t e m . L o c a t e
a n d e l i m i n a t e t h e a i r s o u r c e .
V e r i f y b y i n s p e c t i n g t h e f u e l f i l t e r . C l e a n t h e s y s t e m a n d u s e
c l i m a t i z e d f u e l . R e p l a c e f u e l / w a t e r s e p a r a t o r f i l t e r . C h e c k f u e l
h e a t e r f o r p r o p e r o p e r a t i o n .
V e r i f y b y o p e r a t i n g t h e e n g i n e w i t h c l e a n f u e l f r o m a t e m p o r a r y
s u p p l y t a n k . C h e c k f o r p r e s e n c e o f g a s o l i n e . R e p l a c e f u e l / w a t e r
s e p a r a t o r f i l t e r .
S U R G I N G (SPEED
C H A N G E )
If t h e c o n d i t i o n occurs a t i d l e ,
t h e i d l e s p e e d is s e t t o o l o w f o r
t h e a c c e s s o r i e s .
H i g h p r e s s u r e f u e l l e a k .
O n e or more injectors w o r n o r
not o p e r a t i n g p r o p e r l y .
Improperly o p e r a t i n g injection
pump.
A d j u s t t h e i d l e .
I n s p e c t / c o r r e c t l e a k s i n t h e h i g h p r e s s u r e l i n e s . F i t t i n g s a n d
d e l i v e r y v a l v e s e a l i n g w a s h e r s .
C h e c k / r e p l a c e t h e i n o p e r a t i v e i n j e c t o r s .
Repair or replace the injection pump.
ROUGH IDLE
(IRREGULARLY FIRING
OR ENGINE S H A K I N G )
C o l d e n g i n e .
I d l e s p e e d too l o w f o r t h e
a c c e s s o r i e s .
Engine mounts damaged o r
loose.
Refer t o t r o u b l e s h o o t i n g logic f o r i n t a k e m a n i f o l d h e a t e r s y s t e m
(see G r o u p 1 1 , E x h a u s t S y s t e m I I n t a k e M a n i f o l d )
A d j u s t i d l e s p e e d .
R e p a i r o r r e p l a c e m o u n t s .
J9409-110