1990 MITSUBISHI SPYDER low oil pressure

GENERAL Precautions before Service . .
Caution
1.Before connecting or disconnecting the negative
be sure to turn off the ignition and
the lighting switch.
(if this is not done, the possibility semi-
conductor parts being damaged.)
2.After completion of the work steps [when the bat-
tery’s negative terminal is connected], warm
up the engine and allow it for approximately
five minutes under the conditions be-
low, in order to stabilize the engine condi-
tions, and then check to be sure that idling’ is
satisfactory.
Engine temperature:
Lights, electric fans, accessories: OFF
Transaxle: Neutral position
(A/T models: “N” or “P”)
Steering
neutral (center) position
mm (in.)
Scan tool
ROM pack
VEHICLE WASHING
If high-pressure car-washing equipment or steam car -washing
equipment is used to wash the vehicle, be maintain
the spray nozzle at a distance of at ‘least 300 mm (12 in.)
from any plastic parts and all opening parts (doors , luggage
compartment, etc.).
APPLYING ANTI-CORROSION
OTHER UNDERCOAT AGENTS.,
Be careful not to adhere oil or grease to the heate d oxygen
sensor. If adhered, the sensor may malfunction.
Protect the heated oxygen sensor with a cover befor e applying
anti-corrosion agent, etc.
SCAN TOOL
To operate the scan tool, refer to the “MUT-II OPER ATING
INSTRUCTIONS”.
Caution
Turn the ignition switch off befoie connecting and discon-
necting the scan tool.

GENERAL Maintenance Service
Engine (Non-turbo)>
Engine (Turbo) and Engine>
10. ENGINE OIL FILTER (Replace)
The quality of replacement filters varies considerably.
high quality filters should be used to assure efficient
service.
Genuine oil filters are capable of a pressure,
of 1,765
(256 psi). These high’ quality filters are highly
recommended. The followings part are available as f ollows.
Oil Filter Part No.
Engine (Turbo) and
Mitsubishi Genuine Parts:
35737, 36466, or
Engine (Non-turbo)>:
Chrysler Genuine Parts: or
ENGINE OIL FILTER SELECTION
This vehicle is equipped with a
oil
The same type of replacement filter is recommended a
replacement filter for this vehicle. It is possible ,
in cold weather, that this vehicle may develop high
for a short duration. You should be sure that replacement
filter used on this vehicle is a high-quality filter and is
of withstanding a pressure of1 , 7 6 5 , (256
(manufacturer’s specifications) to avoid filter and engine
damage.
The following is a high-quality filter and is strongly
recommended for use on this vehicle.
Engine (Turbo) and
Mitsubishi Engine Oil Part No;
or
Engine (Non-turbo)>
Chrysler Engine Oil Filter Part No.
Any replacement oil filter should be installed
with the oil filter manufacturer’s installation
(1) Remove the engine oil filler cap.
(2)Remove the engine oil drain plug, out
oil.
(3) Remove the engine oil filter by using the oil f ilter
(4)Clean the oil filter mounting surface of the oil filter bracket.
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GENERAL Maintenance
4.Before removing dipstick, wipe all dirt from area around
dipstick. Then take out the dipstick and check the condition
of the fluid.
Further investigation of the transaxle is necessary if,
l the fluid smells burnt.
l the fluid color is brown or black.
l metal particles can be seen or felt on the dipstick .
5.Check to see if fluid level is in “HOT” range on dipstick.
If fluid level is low, add ATF until level reaches “HOT”
range. Low fluid level can cause a variety of condi tions
because it allows pump to take in air along with fl uid.
Air trapped in hydraulic circuit forms bubbles which make
fluid spongy.
Therefore, pressures will be erratic. Improper filling can also raise fluid level too hig h. When
transaxle has too much fluid, gears churn up foam a nd
cause same conditions which occur with low fluid le vel,
resulting in accelerated deterioration of ATF.
In either case, air bubbles can cause overheating, fluid
-oxidation, which can interfere with normal valve, clutch,
and servo operation. Foaming can also result in flu id
escaping from transaxle vent where it may be mistak en
for a leak.
6. Be sure to examine fluid on dipstick closely.
(Change fluid)
Engine (Non-turbo)>
1.Place a drain container with a large opening, under the
transaxle oil pan.
2. Loosen the pan bolts and tap the
at one comer’
to break it loose allowing fluid to drain, then rem ove the
oil pan.
3. Install a new filter and O-ring on bottom of the valve
body.
4. Clean the oil pan and magnet.
Apply the specified sealant to the oil pan.
Specified sealant: Loctite 18718 or equivalent
Tighten the oil pan mounting bolts to the specified torque:
Tightening torque:
19Nm (14
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ENGINE General Information
GENERAL INFORMATION
Items SpecificationsI
Number of cylinders
Bore mm (in.)
Stroke mm (in.)
In-line DOHC
85.0
(3.28)
Piston displacement
Compression ratio
Firing order
Counterbalance shaft8.5
Equipped
Valve timing Intake valve
Exhaust valve Opens
Closes
Opens
Closes 21 “BTDC
.
Lubrication systemIPressure feed-full flow , ,I
Oil pump type
LUBRICATION SYSTEM
Involute gear type
To
Camshaft
Counterbalance
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Oil
Oil pressure switch
Crankshaft
Counterbalance shaft

ENGINE,
TROUBLESHOOTING
Oil filter cloggedInstall new filter
Oil pump gears or cover wornReplace gears cover
Thin or diluted engine oil Change engine oil to correct viscosity
Oil relief valve stuck (open) Repair relief valve
Excessive bearing clearanceReplace bearings
pressure too high Oil relief valve stuck (closed) Repair relief valve
Joisy valves Incorrect lash adjuster Bleed air or rep lace lash adjuster
Thin or diluted engine oil (low oil pressure)
Change engine oil ,
Valve stem or valve guide worn or damaged Replace va lve guide
rod noise/Insufficient oil supplyCheck engine oil level
nain bearing noise Low oil pressure Refer
pressure drop”
Thin or diluted engine oil Change engine oil
Excessive bearing clearance Replace bearings
belt noiseIncorrect belt tension Adjust belt tension and/or replace tim-ing belt
engine Loose engine roll stopper (Front, Rear)Retighten
ng and vibration
Loose transaxle mount bracketRetighten
Loose engine mount bracketRetighten
Loose center memberRetighten
Broken transaxle mount insulatorReplace
Broken engine mount insulatorReplace
Broken roll stopper insulatorReplace
Symptom
Probable cause
Remedy.
Compression too low Cylinder head gasket blownReplace gasket
Piston ring worn or damagedReplace rings
Piston or cylinder worn
Repair or replace piston cylinder
block
Valve seat worn or damagedRepair or replace valve and/or
Oil pressure drop Engine oil level too low Check engine oil level
Oil pressure switch faulty
pressure switch
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ENGINE On-vehicle
8. If the standard value is exceeded, check the following
items:
l Diagnostic output
l Closed-loop control (When the closed-loop control
is carried out normally, the output signal of the h eated
oxygen sensor repeats between and
,000 at idle.)
l Fuel pressure
I n j e c t o r
lIgnition coil, spark plug cable, spark plug
lEGR system and the EGR valve leak
l Evaporative emission control system
Compression pressure
NOTE
Replace the catalyst whenever the
HC contents do not remain inside the standard value .
(even though the result of the inspection is
all items.).
C O M P R E S S I O N
CHECK
1.Before inspection, check that the engine-oil, start er
battery are normal. Also, set the to the
condition:
lEngine coolant temperature:
lLights, electric cooling fan and all accessories: O FF
lTransaxle: Neutral (P range on vehicles with
2. Disconnect the spark plug cables.
3. Remove all of the spark plugs.
4.
5.
Disconnect the crankshaft position sensor connector .
NOTE
Doing this will prevent the engine control unit fro m carrying
out ignition and fuel injection.
Cover the spark plug hole with a shop towel etc., a nd
after the engine has been cranked, check that no fo reign
material is adhering to the shop towel.
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ENGINE On-vehicle
Caution
1.Keep away from the spark plug hole when crank-
ing.
2. If compression is measured with water, oil, fuel,
etc., that has come from cracks inside the cylinder ,
these materials will become heated and will gush
out from the spark plug hole, which is dangerous.
6.Set compression gauge to one of the spark plug hole s.
7. Crank the engine with the throttle valve fully o pen and
measure the compression pressure.
Standard value (at engine speed of
1,250 (178 psi)
Limit (at engine speed of
min. 935 (133 psi)
8.Measure the compression pressure for all the cylind ers,
and check that the pressure differences of the cylinders
are below the limit.
Limit:. max. 100
(14 psi)
9.If there’ is a cylinder with compression or a compr ession
difference that is outside the limit, pour a small amount
of engine oil through the spark plug hole, and repe at
the operations in steps 7 and
(1) If the compression increases after oil is added , the
cause of the malfunction is a worn or damaged pisto n
ring and/or cylinder inner
(2) If the compression does not rise after oil is added,
the cause is a burnt or defective valve seat,
is leaking from the gasket.
10. Connect the crankshaft position sensor
11. Install the spark plugs and spark plug cables.
12. Use the scan tool to erase the diagnostic
codes,
or disconnect the negative battery cable’ for
than
10 seconds and reconnect it.
NOTE
This will erase the diagnostic trouble code from
the crankshaft position sensor connector being disc on-
nected.
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ENGINE On-vehicle Service
MANIFOLD VACUUM CHECK11100270200
1.Before inspection, set vehicles in the following condition:
lEngine coolant temperature:
lLights, electric cooling fan, and accessories: OFF
l Transaxle: Neutral (P range on vehicles with
2. Set up the tachometer or connect the scan tool t o the
data link connector.
3.Attach a three-way joint to the vacuum hose connect ed
between the intake manifold plenum and the fuel pressure
solenoid valve and connect a vacuum gauge.
4. Start the engine, and check that the curb idle s peed is
within the standard value range.
Standard value: 750
100
5. Check the manifold vacuum.
Limit: min. 60
(18
LASH ADJUSTER CHECK
NOTE
NOTE
If an abnormal noise (rattling noise) probably caus ed by the
If an abnormal noise (rattling noise) probably caus ed by the
lash adjusters is heard and the noise does not
lash adjusters is heard and the noise does not
as follows.
as follows.
1. Check the engine oil, and if required, refuel or replace
it.
NOTE
lIf the amount of the engine oil is insufficient, ai r will
be sucked in from the oil strainer and mix
the oil
passage.
lIf the amount of the engine oil is more than the sp eci-
fied amount, it will be stirred by the crankshaft to
make a lot of air
in the
l If the oil is deteriorated, it will not easily
from air and the amount of air’ mixed in the oil wi ll ,
increase.
If the air which has mixed in the oil due to the ab ove
causes enters the high pressure chamber in the lash
adjusters, the air in the high pressure chamber wil l be
pressurized during opening of the valve, which caus es
the lash adjusters to shrink excessively, and an abnormal
noise will be generated when the valve is closed. T his
is the same phenomenon as the one when the valve
clearance has been excessively adjusted by mistake.
In this case, if the air which has entered the lash adjusters
is bled, things will be normalized.
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