
The MOPAR Silicone Rubber Adhesive Sealant
gasket material or equivalent should be applied in a
continuous bead approximately 3mm (0.120 inch) in
diameter. All mounting holes must be circled. For
corner sealing, a 3.17 or 6.35 mm (1/8 or 1/4 inch.)
drop is placed in the center of the gasket contact
area. Uncured sealant may be removed with a shop
towels. Components should be torqued in place while
the sealant is still wet to the touch (within 10 min-
utes). The usage of a locating dowel is recommended
during assembly to prevent smearing of material off
location.
CRANKSHAFT SPROCKET BOLT ACCESS PLUG
An Access plug is located in the right inner fender
shield. Remove the plug and insert proper size
socket, extension and rachet, when crankshaft rota-
tion is necessary.
ENGINE PERFORMANCE
If a loss of performance is noticed, ignition timing
should be checked. If ignition timing is retarded by
9, 18 or 27É indicating 1, 2 or 3 (timing belt or chain)
teeth may have skipped, then, camshaft and acces-
sory shaft timing with the crankshaft should be
checked. Refer to Engine Timing Sprockets and Oil
Seals of the Engine Section. To provide best vehicle performance and lowest ve-
hicle emissions, it is most important that the tune-up
be done accurately. Use the specifications listed on
the Vehicle Emission Control Information label
found in the engine compartment. (1) Test cranking amperage draw. See Starting
Motor Cranking Amperage Draw Electrical Section
of this manual. (2) Tighten the intake manifold bolts to specifica-
tions. (3) Perform cylinder compression test.(a) Check engine oil level and add oil if neces-
sary. (b) Drive the vehicle until engine reaches normal
operating temperature. (c) Select a route free from traffic and other
forms of congestion, observe all traffic laws, and ac-
celerate through the gears several times briskly.
CAUTION: Do not overspeed the engine. The higher
engine speed may help clean out valve seat deposits
which can prevent accurate compression readings.
(d) Remove all spark plugs from engine. As
spark plugs are being removed, check electrodes for
abnormal firing indicators fouled, hot, oily, etc.
Record cylinder number of spark plug for future
reference. (e) Disconnect coil wire from distributor and se-
cure to good ground to prevent a spark from start- ing a fire (Conventional Ignition System). For Direct
Ignition System DIS disconnect the coil connector. (f) Be sure throttle blade is fully open during the
compression check. (g) Insert compression gage adaptor into the #1
spark plug hole in cylinder head. Crank engine until
maximum pressure is reached on gage. Record this
pressure as #1 cylinder pressure. (h) Repeat Step G for all remaining cylinders.
(i) Compression should not be less than (689kPa)
100 psi and not vary more than 25 percent from
cylinder to cylinder. (j) If one or more cylinders have abnormally low
compression pressures, repeat steps 3b through 3h. (k) If the same cylinder or cylinders repeat an
abnormally low reading on the second compression
test, it could indicate the existence of a problem in
the cylinder in question.
The recommended compression pressures are
to be used only as a guide to diagnosing engine
problems. An engine should not be disassembled
to determine the cause of low compression un-
less some malfunction is present. (4) Clean or replace spark plugs as necessary and
adjust gap as specified in Electrical Group 8. Tighten to
specifications. (5) Test resistance of spark plug cables. Refer to
Ignition System Secondary Circuit Inspection Electri-
cal Section Group 8. (6) Inspect the primary wire. Test coil output volt-
age, primary and secondary resistance. Replace parts
as necessary. Refer to Ignition System and make nec-
essary adjustment. (7) Ignition timing should be set to specifications.
(See Specification Label in engine compartment). (8) Test fuel pump for pressure and vacuum. Refer to
Fuel System Group 14, Specifications. (9) The air filter elements should be replaced as
specified in Lubrication and Maintenance, Group 0. (10) Inspect crankcase ventilation system as out
lined in Lubrication and Maintenance, Group 0. For
emission controls see Emission Controls Group 25 for
service procedures. (11) Inspect and adjust accessory belt drives refer-
ring to Accessory Belt Drive in Cooling System, Group
7 for proper adjustments. (12) Road test vehicle as a final test.
HONING CYLINDER BORES
Before honing, stuff plenty of clean shop towels
under the bores, over the crankshaft to keep abrasive
materials from entering crankcase area. (1) Used carefully, the cylinder bore resizing hone
C-823 equipped with 220 grit stones, is the best tool for
this job. In addition to deglazing, it will reduce taper
and out-of-round as well as removing light
9 - 2 ENGINE Ä

shaft end play. A sintered iron (TBI engine and steel
billet Turbo III engines) timing belt sprocket is
mounted on the cam nose, and a hydrodynamic oil
seal is used for oil control at the front of the cam-
shaft. ACCESSORY SHAFT: The iron accessory shaft
has two bearing journals and is housed in the for-
ward facing side of the block. A hydrodynamic seal,
installed in an aluminum housing attached to the
block, provides retention, shaft thrust, and oil con-
trol. The accessory shaft is driven by the timing belt
through a sintered iron (TBI engine and steel billet
Turbo III engines) sprocket mounted on the nose of
the accessory shaft. The accessory shaft in turn
drives the oil pump and distributor on 2.2/2.5L and
2.5L FFV and the oil pump only on Turbo III. VALVES: The valves are actuated by roller cam
followers which pivot on stationary hydraulic lash
adjusters. The valve train with 40.6 mm (1.60 inch)
diameter intake valves and 35.4 mm (1.39 inch) di-
ameter exhaust valves employ viton rubber valve
stem seals except 2.5L FFv . the 2.5L FFV valve
stem seals are made of special rubber compound
which resist the deteriorating effects of methanol
fuel by-products that enter the oil during combus-
tion. Valve springs, spring retainers, and locks are
conventional. For Turbo III engines the valves are
actuated by roller tipped rocker arms with hydraulic
lash adjusters which pivot on a shaft. The valve train
with 33.88 mm (1.33 in.) diameter intake valves are
arranged in line opposite of the 29.26 mm (1.15 in.)
diameter exhaust valves employ locking valve stem
seals. Valve springs, spring retainers, and locks are
not interchangeable with other engines. BALANCE SHAFTS: 2.2 Turbo III and 2.5L en-
gines are equipped with two counter rotating balance
shafts installed in a carrier attached to the lower
crankcase. The shafts are interconnect through
gears. These gears are driven by a short chain from
the crankshaft, to rotate at two times crankshaft
speed. This counterbalances certain engine recipro-
cating forces. INTAKE MANIFOLDS:
All intake manifolds are
aluminum castings, attached to the cylinder head
with eight bolts. N.A. engines use a four branch de-
sign. This long branch fan design enhances low and
midspeed torque. It also features an integrally cast
water crossover passage to warm incoming fuel/air
mixture, plus an EGR mounting boss and PCV inlet. The Turbo III engine intake manifold is a log type
with tuned runners. The manifold is machined to ac-
cept fuel injectors near the ports of each cylinder. EXHAUST MANIFOLDS: The exhaust manifolds
are made of nodular cast iron for strength and high
temperatures. All naturally aspirated (N.A.) and tur-
bocharged engines exit exhaust gasses through a ma-
chined, articulated joint connection to the exhaust
pipe. 2.2/2.5L and 2.5L FFV manifolds intermesh
with the intake manifold at the cylinder head. N.A. engines use a four branch design with cylin-
ders one and four joined and cylinder two and three
joined to exit at the outlet. The Turbo III engine exhaust manifold also carries
the turbocharger. This manifold has a modified log
type collector with exhaust gasses directed to and
through the turbocharger to exit the conical (articu-
lated joint) outlet machined into the turbocharger ex-
haust elbow. ENGINE LUBRICATION: Refer to Group 0 Lu-
brication and Maintenance for recommended oil to be
used in various engine application. System is full
flow filtration, pressure feed type. The oil pump is
mounted within the crankcase and driven by the ac-
cessory shaft. Pressurized oil is then routed through
the main oil gallery, running the length of the cylin-
der block, supplying main and rod bearings with fur-
ther routing (for 2.2L turbo III and 2.5L engines) to
the lower balance shaft assemblies. Pistons are lubri-
cated from directed holes in the connecting rod as-
semblies. Camshaft and valve mechanisms are
lubricated from a full-length cylinder head oil gallery
supplied from the crankcase main oil gallery.
9 - 10 2.2/2.5L ENGINE Ä

(15) Install rocker arm covers tighten screws to 14
N Im (120 in. lbs.) and connector to ignition coils.
(16) Install Intake Manifold; Refer to Intake Mani-
fold Installation 3.3/3.8L Engine, Group 11 Exhaust
System and Intake Manifold.
HYDRAULIC TAPPETS
The valve train includes roller tappet assemblies,
aligning yokes and yoke retainer. Roller tappet alignment is maintained by machined
flats on tappet body being fitted in pairs into six
aligning yokes. The yokes are secured by an alignment
yoke retainer (Fig. 26).
PRELIMINARY STEP TO CHECKING THE HY- DRAULIC TAPPETS
Before disassembling any part of the engine to cor-
rect tappet noise, read the oil pressure at the gauge.
Install a reliable gauge at pressure sending unit if
vehicle has no oil pressure gauge and check the oil level
in the oil pan. The pressure should be between 30 and
80 psi (206.8 to 551.6 kPa) at 2000 rpm. The oil level in the pan should never be above the
MAX mark on dipstick, or below the MIN mark. Either
of these two conditions could be responsible for noisy
tappets. Oil Level Check: stop engine after reach-
ing normal operating temperature . Allow 5 min-
utes to stabilize oil level, check dipstick.
OIL LEVEL TOO HIGH
If oil level is above the MAX mark on dip stick, it is
possible for the connecting rods to dip into the oil while
engine is running and create foam. Foam in oil pan
would be fed to the hydraulic tappets by the oil pump
causing them to become soft and allow valves to seat
noisily.
OIL LEVEL TOO LOW
Low oil level may allow pump to take in air which
when fed to the tappets, causes them to become soft
and allows valves to seat noisily. Any leaks on intake
side of pump through which air can be drawn will
create the same tappet action. Check the lubri- cation system from the intake strainer to the pump
cover, including the relief valve retainer cap. When
tappet noise is due to aeration, it may be intermittent
or constant, and usually more than one tappet will be
noisy. When oil level and leaks have been corrected,
engine should be operated at fast idle to allow all of the
air inside of the tappets to be bled out.
VALVE TRAIN NOISE DIAGNOSIS
To determine source of valve train noise, operate
engine at idle with cylinder head covers removed and
listen for source of the noise. Worn valve guides or cocked springs are some-
times mistaken for noisy tappets. If such is the
case, noise may be dampened by applying side
thrust on the valve spring. If noise is not appre-
ciably reduced, it can be assumed the noise is in
the tappet. Inspect the rocker arm push rod
sockets and push rod ends for wear. Valve tappet noise ranges from light noise to a heavy
click. A light noise is usually caused by excessive
leakdown around the unit plunger which will necessi-
tate replacing the tappet, or by the plunger partially
sticking in the tappet body cylinder. A heavy click is
caused either by a tappet check valve not seating, or by
foreign particles becoming wedged between the
plunger and the tappet body causing the plunger to
stick in the down position. This heavy click will be
accompanied by excessive clearance between the valve
stem and rocker arm as valve closes. In either case,
tappet assembly should be removed for inspection and
cleaning.
TAPPET REMOVAL
(1) Refer to Cylinder Head Removal of this section to
remove intake manifold and cylinder heads for access
to tappets for service. (2) Remove yoke retainer and aligning yokes.
(3) Use Tool C-4129 to remove tappets from their
bores. If all tappets are to be removed, identify tappets
to insure installation in original location. If the tappet or bore in cylinder block is scored,
scuffed, or shows signs of sticking, ream the bore
to next oversize and replace with oversize tap-
pet.
CAUTION: The plunger and tappet bodies are not
interchangeable. The plunger and valve must always
be fitted to the original body. It is advisable to work on
one tappet at a time to avoid mixing of parts. Mixed
parts are not compatible. Do not disassemble a tap-
pet on a dirty work bench.
DISASSEMBLY (FIG. 27)
(1) Pry out plunger retainer spring clip.
Fig. 26 Roller Tappets Aligning Yoke and Retainer
9 - 108 3.3/3.8L ENGINE Ä

(2) Clean varnish deposits from inside of tappet
body above plunger cap. (3) Invert tappet body and remove plunger cap,
plunger, flat or ball check valve, check valve spring,
check valve retainer and plunger spring. Check valve
could be flat or ball.
CLEANING AND ASSEMBLY
(1) Clean all tappet parts in a solvent that will re-
move all varnish and carbon. (2) Replace tappets that are unfit for further ser-
vice with new assemblies. (3) If plunger shows signs of scoring or wear, valve
is pitted, or valve seat on end of plunger indicates
any condition that would prevent valve from seating,
install a new tappet assembly. (4) Assemble tappets (Fig. 27).
INSTALLATION
(1) Lubricate tappets.
(2) Install tappets in their original positions.
(3) With roller tappets, install aligning yokes with
(Fig. 26). (4) Install yoke retainer and torque screws to 12
N Im (105 in. lbs.) (Fig. 26).
(5) Install cylinder heads. Refer to cylinder head
installation of this section for procedure. (6) Start and operate engine. Warm up to normal
operating temperature.
CAUTION: To prevent damage to valve mechanism,
engine must not be run above fast idle until all hy-
draulic tappets have filled with oil and have become
quiet.
VALVE TIMING
(1) Remove front valve cover and all 6 spark plugs.
(2) Rotate engine until the #2 piston is at TDC of
the compression stroke. (3) Install a degree wheel on the crankshaft pulley.
(4) With proper adaptor, install a dial into #2
spark plug hole. Using the indicator find TDC on the
compression stroke. (5) Position the degree wheel to zero.
(6) Remove dial indicator from spark plug hole. (7) Place a 5.08mm (.200 inch) spacer between the
valve stem tip of #2 intake valve and rocker arm
pad. Allow tappet to bleed down to give a solid tap-
pet effect. (8) Install a dial indicator so plunger contacts the
#2 intake valve spring retainer as nearly perpendic-
ular as possible. Zero the indicator. (9) Rotate the engine clockwise until the in take
valve has lifted .254mm (0.010 inch).
CAUTION: Do not turn crankshaft any further clock-
wise as intake valve might bottom and result in se-
rious damage.
(10) Degree wheel should read 3 degrees BTDC to
4 degrees ATDC.
TIMING CHAIN COVER, OIL SEAL AND CHAIN
COVER
REMOVAL
(1) Disconnect battery.
(2) Drain cooling system. Refer to Cooling System
Group 7 for procedure. (3) Support engine and remove right engine
mount. (4) Raise vehicle on hoist. Drain engine oil.
(5) Remove oil pan and oil pump pick-up. It may
necessary to remove transmission inspection cover. (6) Remove right wheel and inner splash shield.
(7) Remove drive belt. Refer to Cooling System
Group 7 for procedure. (8) Remove A/C compressor and set aside.
(9) Remove A/C compressor mounting bracket.
(10) Remove crankshaft pulley (Fig. 1).
(11) Remove idler pulley from engine bracket.
(12) Remove engine bracket (Fig. 2).
(13) Remove cam sensor from chain case cover
(Fig. 3).
Fig. 27 Hydraulic Roller Tappet Assembly
Fig. 1 Removing Crankshaft Pulley
Ä 3.3/3.8L ENGINE 9 - 109

(7) Disconnect Intercooler to throttle body outlet
hose. Disconnect vacuum hoses from throttle body
and remove harness (Fig. 5).
(8) Disconnect automatic idle speed (AIS) motor
and throttle position sensor (TPS) wiring connectors
(Fig. 6). (9) Remove PCV Breather/Separator box and vac-
uum harness assembly. Remove brake booster, vac-
uum vapor harness and fuel pressure regulator
harness from intake manifold (Fig. 7). (10) Disconnect Fuel Injector Wiring Connector
(Fig. 8). Charge Temperature Wiring Connector (Fig.
7). (11) Remove fuel supply and return hose quick
connect at fuel tube assembly (Fig. 9). WARNING: WRAP SHOP TOWELS AROUND HOSES
TO CATCH ANY GASOLINE SPILLAGE
.
(12) Remove 8 intake manifold screws and washer
assemblies and remove intake manifold (Fig. 10).
INSTALLATION
Before installing manifold. Refer to Cleaning and
Inspection of this section to check manifold for dam-
age. (1) Install new intake manifold gasket and intake
manifold onto cylinder head and tighten fasteners to
23 N Im (200 in. lbs.) torque (Fig. 10).
(2) Install PCV Breather/Separator box and vac-
uum harness assembly. Connect brake booster, vac-
uum vapor harness and vacuum hose to fuel pressure
regulator (Fig. 7).
Fig. 1 Air Cleaner and Throttle Body AssemblyÐTurbo III Engine
Fig. 2 Radiator to Cylinder Head Hose
Fig. 3 Distributorless Ignition Coil (DIS) Location
Fig. 4 Accelerator and Speed Control Cables
11 - 10 EXHAUST SYSTEM AND INTAKE MANIFOLD Ä

(3) Inspect quick connect fittings for damage, re-
place if necessary Refer to Fuel System, Group 14 for
procedure. Lube tube with clean 30w engine oil, Con-
nect fuel supply and return hoses to chassis tube as-
sembly. Check connection by pulling on connector to
insure it locked into position (Fig. 9). (4) Connect Fuel Injector (Fig. 8), and Charge
Temperature Sensor wiring connectors (Fig. 7).
INTAKE MANIFOLD
(5) Connect Automatic Idle Speed (AIS) and Throt-
tle Position Sensor (TPS) wiring connectors (Fig. 6). (6) Connect vacuum hoses to throttle body (Fig. 5).
(7) Install intercooler to throttle body hose and
clamp. Torque clamp to 3 N Im (30 in. lbs.) (Fig. 5). (8) Connect accelerator and speed control cables
(Fig. 4). (9) Install DIS ignition coil pack. Tighten fasteners
to 12 N Im (105 in. lbs.) torque (Fig. 3).
(10) Install upper radiator hose and spring clamps
(Fig. 2). Fill cooling system, Refer to Cooling System,
Group 7. (11) Install fresh air duct to air filter housing. In-
stall inlet hose assembly to Intercooler. Tighten
clamp to 3 N Im (30 in. lbs.) torque (Fig. 1).
(12) Connect negative battery cable.
(13) With the DRBII Scan Tool use ASD Fuel Sys-
tem Test to pressurize system to check for leaks.
Fig. 5 Intercooler to Throttle Body Hose
Fig. 6 Automatic Idle Speed (AIS) Motor and
Throttle Position Sensor (TPS) Wiring Connectors
Fig. 7 Intake Manifold Electrical and Vacuum Hose Connections
Fig. 8 Camshaft Sensor and Fuel Injectors WiringConnectors
Ä EXHAUST SYSTEM AND INTAKE MANIFOLD 11 - 11

place. Install attaching fasteners (8) and tighten in
several steps in sequence shown (Fig. 17) to 13 N Im
(115 in. lbs.). (13) Connect fuel line to fuel rail (Fig. 7). Torque
hose clamps to 1 N Im (10 in. lbs.).
(14) Connect vacuum harness to air intake ple-
num. (15) Connect coolant temperature sensor electrical
connector to sensor (Fig. 7). (16) Connect PCV and brake booster supply hose
to intake plenum. (17) Connect automatic idle speed (AIS) motor and
throttle position sensor (TPS) electrical connectors
(Fig. 5). (18) Connect vacuum vapor harness to throttle
body (Fig. 5). (19) Install throttle cable and transaxle kickdown
linkage (Fig. 4). (20) Install air inlet hose assembly (Fig. 3).
(21) Install radiator to thermostat housing hose
and heater hose to heater pipe nipple. (22) Fill cooling system, see Refilling System in
Cooling, Group 7. (23) Connect negative battery cable.
(24) With the DRBII Scan Tool use ASD Fuel Sys-
tem Test to pressurize system to check for leaks.
Fig. 5 Electrical and Vacuum Connections to Throttle Body
Fig. 6 Ignition Coil Removal
Fig. 7 Coolant Temperature Sensor Electrical Connections
Fig. 8 Air Intake Plenum to Intake ManifoldAttaching Bolts
Fig. 9 Removing Air Intake Plenum
11 - 16 EXHAUST SYSTEM AND INTAKE MANIFOLD Ä

(12) Remove the fuel hose quick connect fittings
from the fuel rail using an open end wrench to push
in on the plastic ring located on the end of the fit-
tings. Gently pull the fittings from the fuel rail (Fig.
7).
WARNING: WRAP A SHOP TOWEL AROUND
HOSES TO CATCH ANY GASOLINE SPILLAGE.
(13) Remove direct ignition system (DIS) coils and
generator bracket to intake manifold bolt (Fig. 8). (14) Remove intake manifold bolts and rotate man-
ifold back over rear valve cover (Fig. 9). (15) Cover intake manifold with suitable cover
when servicing (Fig. 10). (16) Remove vacuum harness connector from Fuel
Pressure Regulator. (17) Remove fuel tube retainer bracket screw and
fuel rail attaching bolts (Fig. 10). Spread the retainer
bracket to allow fuel tube removal clearance. (18) Remove fuel rail injector wiring clip from the
generator bracket (Fig. 11). (19) Disconnect cam sensor, coolant temperature
sensor, and engine temperature sensors. (20) Remove fuel injector wiring clip from intake
manifold water tube. (21) Remove fuel rail. Be careful not to damage
the rubber injector O-rings upon removal from their
ports (Fig. 12). (22) Remove upper radiator hose, bypass hose and
rear intake manifold hose (Fig. 13). (23) Remove intake manifold bolts. Remove intake
manifold. (24) Remove intake manifold seal retainers screws
(Fig. 14). Remove intake manifold gasket.
INSPECTION
Check for:
² Damage and cracks of each section.
Fig. 7 Quick Connect Fuel Fittings to Fuel Rail
Fig. 8 Ignition Coils
Fig. 9 Intake Manifold Bolts
Fig. 10 Fuel Rail Attaching Bolts
Ä EXHAUST SYSTEM AND INTAKE MANIFOLD 11 - 21