1988 PONTIAC FIERO oil

ENGINE GENERAL INFORMATION 6-3
B, Section 6E2 - Fuel Injection (TBI)
B, Section 6E3 - Fuel Injection (Ported)
ENGINE MECHANICAL DIAGNOSIS
The following diagnostic information covers common problems and possible causes. When
the proper diagnosis is made, the problem should be corrected by adjustment, repair or part
replacement as required. Refer to the appropriate section of the manual for these procedures.
EXCESSIVE OIL LOSS
B, External oil leaks. Tighten bolts and/or replace o Continuous high speed driving, and/or severe
gaskets and seals as necessary. usage
such as trailer hauling, will normally cause
decreased oil mileage.
e Improper reading of dipstick. Check oil with car PCV system malfunctioning. on a level surface and allow adequate drain-down Valve guides and/or valve stem seals worn, or time.
seals omitted. Ream guides and install oversize
service valves and/or new valve stem seals.
Improper Use S.A'E' Piston rings broken, worn, or not seateded. Allow viscosity for prevailing temperatures. See
adequate time for rings to seat. Replace broken
Owner's Manual for proper specifications.
or worn rings, as necessary.
Piston improperly installed or misfitted.
LOW OIL PRESSURE
Slow idle speed. Set idle speed to correct
specification, if not ECM controlled.
Incorrect, or malfunctioning, oil pressure switch.
Incorrect, or malfunctioning, oil pressure gage.
Replace with proper gage.
.*
Improper oil viscosity, or diluted oil. install oil of
proper viscosity for expected temperature, or
install new oil if diluted with moisture or
unburned fuel mixtures.
o Oil pump worn or dirty.
e Plugged oil filter.
e Oil pickup screen loose or plugged.
B, Hole in oil pickup tube.
e Excessive bearing clearance. Replace if necessary.
o Cracked, porous or plugged oil galleys. Repair or
replace block.
o Galley plugs missing or misinstalled. Install
plugs, or repair as necessary.
VALVE TRAIN NOISE
e Low oil pressure. Repair as necessary. (See o Broken valve spring.
preceding diagnosis for low oil pressure.)
o Sticking valves.
o Loose rocker arm attachments. Inspect and B, Lifters worn, dirty, or defective. Clean, inspect,
test and replace as necessary.
repair as necessary.
o Camshaft worn, or poor machining. Replace
o Worn rocker arm and/or pushrod. camshaft.
B, Worn valve guides.
ENGINE KNOCK DIAGNOSIS
KNOCKS COLD AND CONTINUES FOR TWO TO THREE MINUTES
INCREASES
WITH TORQUE
o Vacuum operated EFE engines may have valve o Excessive piston to bore clearance. Replace
knock. Replace EFE valve. piston.
e Flywheel contacting splash shield. Reposition
splash shield.
e Loose or broken balancer or drive pulleys.
Tighten, or replace as necessary. Cold engine piston knock usually
disappears when the cylinder is grounded
out. Cold engine piston knock which
disappears in 1.5 minutes should be
considered acceptable.

6-4 ENGINE GENERAL INFORMATION
Bent connecting rod.
HEAVY KNOCK H0"FVVI"F TORQUE APPLIED
Broken balancer, or pulley hub. Replace parts as e Exhaust system grounded. Reposition as
necessary. necessary.
Loose torque converter bolts. Flywheel
cracked.
e Excessive main bearing clearance. Replace as
Accessory belts too tight or nicked. Replace
necessary.
and/or tension to specs as necessary.
e Excessive rod bearing clearance. Replace as
necessary.
LIGHT KNOCK HOT
Detonation or spark knock. Check operation of e Loose torque converter bolts.
EST or ESC (See Section
6D or 6E). Check e Exhaust leak at manifold. Tighten bolts and/or
engine timing and fuel quality.
replace gasket.
8 Excessive rod bearing clearance. Replace
bearings as necessary.
KNOCKS ON INITIAL START-UP BUT ONLY LASTS A FEW SECONDS
Noisy mechanical fuel pump. Replace pump.
When the engine is stopped, some valves
will be open. Spring pressure against lifters
Improper oil viscosity. Install proper oil viscosity will
tend to bleed lifter down. Attempts to
for expected temperatures. See Owner's Manual. repair
should be made only if the problem
is consistent.
Hydraulic lifter bleed down. Clean, test and @ Excessive crankshaft end clearance. Replace
replace as necessary. crankshaft
thrust bearing.
@ Excessive front main bearing clearance. Replace
worn parts.
KNOCKS AT IDLE HOT
Loose or worn drive belts. Tension and/or @ Excessive piston pin clearance. Ream and install
replace as necessary. oversize pins. (VIN R and 2) or replace piston
A/C Compressor or generator bearing. Replace and
pin.
as necessary.
e Connecting rod alignment. Check and replace
rods as necessary.
Noisy mechanical fuel pump. Replace pump.
8 Insufficient piston to bore clearance. Hone bore
Valve train. Replace parts as necessary. and
fit new piston.
@ Loose crankshaft balancer. Torque and/or
Improper oil viscosity. Install proper viscosity oil
replace worn parts.
for expected temperature4 See Owner" e Piston pin offset to wrong side. Install correct
ENGINE OVERHEATS
Coolant system leak, oil cooler system leak, or
2. Belt slipping or damaged. Replace tensioner, or
coolant recovery system not operating. Check for belt, as required.
leaks and correct as required. Check coolant
3. Thermostat stuck closed. Check and replace if
recovery tank, hose and radiator cap.
required.
4. Electrical cooling fan operation. See the
ELECTRICAL TROUBLESHOOTING
MANUAL.
5. Head gasket leaking. Check and repair as
required.

ENGINE GENERAL INFORMATION 6-5
INSTRUMENT PANEL OIL WARNING LAMP "ON" AT IDLE
1. Oil cooler, or oil or cooler line restricted. Remove 2. Oil pump pressure low. See oil pump repair
restrictions in cooler or cooler line. procedures
in Section
6A.
ENGINE COMPRESSION EST
COMPRESSION TEST
Important
e Disconnect the "BAT." terminal from the - HE1 distributor or ignition module.
To determine if the valves or pistons are at fault,
a test should be made to determine the cylinder
compression pressure. When checking cylinder
compression, the throttle and choke should be open, all
spark plugs removed, and the battery at or near full
charge. The lowest reading cylinder should not be less
than
70% of the highest and no cylinder reading
should be less than
689 kPa (100 PSI). This
should be done with four
"puffs" per
cylinder.
Normal - Compression builds up quickly and
evenly to specified compression on each cylinder.
Piston Rings - Compression low on first
stroke, tends to build up on following strokes, but does
not reach normal. Improves considerably with addition
of oil.
Valves - Low on first stroke, does not tend to
build up on following strokes. Does not improve much
with addition of oil.
Use approximately three squirts from a plunger
type oiler.

2.8 LITER V-6 BA2-1
TER V-6 V N CODES RPO
CONTENTS
GENERAL DESCRIPTION ........................ 6A2- 1
ENGINE LUBRICATIONS ......................... 6A2- 1
ON-VEHICLE SERVICE ............................. 6A2-7
Powertrain Mounts .................................... 6A2-7
Rocker Arm Cover .................................... 6A2-8
Intake Manifold .......................................... 6A2-9
Exhaust Manifold ................................... 6A2-9
Rocker Arm and Push Rod ....................... 6A2- 10
Valve Mechanism
....................................... 6A2- 10
Valve Stem Oil Seal and/or Valve
Spring
.................... .. .. ... ................... 6A2- 10
Valve Lifters
............................................. 6A2- l l
Cylinder Head ............................................ 6A2- 12
Rocker Arm Studs
.................................... 6A2- 13
Valve Guides
........................................... 6A2- 13
Valve Seats
................................................ 6A2- 14
Valves
......................................................... 6A2- 14
Torsional Damper
..................................... 6A2- 14 Crankcase
Front Cover
.............................. 6A2- 15
Oil Seal (Front Cover)
........................... .... 6A2- 15
Timing Chain
& Sprocket .......................... 6A2- 15
Camshaft
................................................... 6A2- 16
Camshaft Bearings
................................... 6A2- 16
Oil Pan
........................................................ 6A2- 17
Oil Pump
.................................................. 6A2- 18
Connecting Rod Bearings .......................... 6A2- 18
Main Bearings
............................................ 6A2- 19
Oil Seal (Rear Main)
.................................. 6A2-2 1
Pistons, Rings & Connecting Rods ........... 6A2-2 1
Honing or Reboring Cylinders .................. 6A2-23
Fitting Pistons ............................................ 6A2-24
.............................................. Piston Rings 6A2-24
Engine Assembly ...................................... 6A2-25
.................................................. Crankshaft 6A2-25
........................................ Sprocket or Gear 6A2-26
..................................... SPECIFICATIONS 6A2-26
GENERAL DESCRIPTION
CYLINDER BLOCK
The cylinder block is made of alloy cast iron and
has 6 cylinders arranged in a "V" shape with 3
cylinders in each bank. The cylinder banks are set at
a
60" angle from each other.
The right bank cylinders are
1, 3, 5. Cylinders 2,
4, 6 are on the left bank.
Four main bearings support the crankshaft which
is retained by bearing caps that are machined with the
block for proper alignment and clearances.
CYLINDER HEAD
The cast alloy iron cylinder heads have individual
intake and exhaust ports for each cylinder. Valve
guides are integral, and rocker arms are retained on
individual threaded studs.
CRANKSHAFT AND BEARINGS
The crankshaft is cast nodular iron with deep
rolled fillets on all six crankpins and two center main
journals. Four steel backed aluminum bearings are
used, with
#3 bearing being the end-thrust bearing.
CAMSHAFT AND DRIVE
sprocket is also hardened sintered iron, and is pressed
onto the nose of the crankshaft.
A rubber snubber is
used to dampen chain motion.
PISTONS AND CONNECTING RODS
The pistons are cast aluminum with steel struts
using two compression rings and one coil control ring.
The piston pin is offset
1.5mm towards the major
thrust side. This allows a gradual change in thrust
pressure against the cylinder wall as the piston travels
its path. Pins are chromium steel and have a floating
fit in the pistons. They are retained in the connecting
rods by a press fit.
Connecting rods are made of forged steel. Full
pressure lubrication is directed to the connecting rods
by drilled oil passages from the adjacent main bearing
journal.
VALVE TRAIN
A very simple ball pivot-type train is used.
Motion is transmitted from the camshaft through the
hydraulic lifter and push rod to the rocker arm. The
rocker arm
~ivots on its ball and transmits the
camshaft
mot'ion to the valve. The rocker arm ball
locates on a stud, threaded into the head, and is
The camshaft is cast alloy iron with tapered 13. by a nut. The push rod is located by a guide
2mm wide lobes, offset from the lifters and tapered to plate held under the rocker arm stud, assuring that the
provide positive valve lifter rotation. The camshaft is arm Operates in the plane the
support& by four journals and includes a
distributor/oil pump drive gear, and fuel pump INTAKE MANIFOLD - - eccentric.
The intake manifold is a three piece cast
A
3/8" pitch chain drives the camshaft through
aluminum unit. It centrally supports a fuel rail with 6
a hardened sintered iron sprocket. The crankshaft
fuel injectors.

6A2-2 2.8 LITER V-6
EXHAUST MANIFOLDS
The exhaust manifolds are cast nodular iron.
ENGINE LUBRICATION (FIGURES 6A2.1 THRU
6A2-4)
Full pressure lubrication, through a full flow oil
filter is furnished by a gear type oil pump. Oil is drawn
up through the pick up screen and tube and passed
through the pump to the oil filter.
The oil filter is a full flow paper element unit. An
oil filter by-pass is used to ensure adequate oil supply
should the filter develope excessive pressure drop. The
by-pass is designed to open at 69-83
kPa.
From the filter, oil is routed to the main oil
gallery, rifle drilled above the camshaft to the left of the
camshaft centerline. This gallery supplies the left bank
hydraulic lifters with oil. From
the left gallery oil is directed, by means of
interesting passages to the camshaft bearings and right
oil gallery.
The hydraulic lifters pump oil up through the
push rods to the rocker arms. Oil draining back from
the rocker arms is directed, by cast dams which are
part of the crankcase casting, to supply the camshaft
lobes.
The passages supplying oil to the camshaft
bearings also supply the crankshaft main bearings
through intersecting vertical drilled holes. Oil from the
crankshaft main bearings is supplied to the connecting
rod bearings by means of intersecting passages drilled
in the crankshaft.
Oil also drains past specific hydraulic lifter flats
to oil camshaft .lobes directly.
The front cam bearing has a
.25mm deep slot on
its outside diameter to supply oil to the cam sprocket
thrust face.

LUBRICATION FOR CYL'S
1,3 &5
VIEWS SHOWING INTERMInENT OILING OF
CONNECTING ROD BEARING THROUGH GROOVE
ON UPPER HALF
OF MAIN BEARINGS.

6A2-8 2.8 LITER V-6
6. Install new mount.
7. Lower transmission.
8. Torque nuts to specifications.
Figure 6A2-6 Rocker Arm Cover
ROCKER ARM COVER
Removal (Left)
1. Disconnect battery.
2. Disconnect air management hose (manual
transmission only).
3. Remove plenum and runners and disconnect
throttle body per Section
6E3.
4. Remove A/C bracket.
5. Remove rocker cover reinforcements and nuts.
6. Remove cover. If cover adheres to cylinder head,
shear off by bumping end of rocker arm cover
with palm of hand or rubber mallet. If cover still
will not come loose, CAREFULLY pry until
loose. DO NOT DISTORT SEALING
FLANGE. It may be necessary to remove the two
spark plug wire harness studs in order to get the
rocker cover past the windshield wiper motor.
Installation (Left)
1. Clean sealing surface on cylinder head, intake
manifold and rocker cover. Make sure sealing
flange or rocker cover is not bent.
2. Place a 3mm diameter
(1/8") dot of RTV sealant,
# 1052917 or equivalent, at the intake manifold
and cylinder head splitline.
3. Install rocker cover gasket over studs in the
manifold and cylinder head.
4. Install the reinforcements and nuts and torque to
8-20
N.m (6-14 ft. lbs.).
5. Install the plenum and runners and connect the
throttle body as per Section
6E3.
6. Connect air management hose (manual
transmission only).
7. Install
A/C bracket.
8. Connect battery.
Removal (Right)
1. Disconnect battery. 2.
Remove EGR valve transfer tube from plenum.
3. Remove coil and coil mounting bracket from
cylinder head.
4. Remove plenum and runners and disconnect
throttle body per Section
6E3.
5. Remove rocker cover retainers and nuts.
6. Remove cover. If cover adheres to cylinder head,
shear off by bumping end of rocker cover with
palm of hand or rubber mallet. If cover still does
not come loose, CAREFULLY pry until loose.
DO NOT DISTORT SEALING FLANGE.
Installation (Right)
Clean sealing surface on cylinder head, intake
manifold, and rocker cover. Make sure sealing
flange or rocker cover is not bent.
Place a 3mm diameter
(1/8") dot of RTV sealant,
# 1052917 or equivalent, at the intake manifold
and cylinder head splitline.
Install rocker cover gasket over studs in the
manifold and cylinder head.
Install the load spreaders and nuts and torque to
90 in. lbs.
Install plenum and runners and connect throttle
body per Section
6E3.
Install coil and coil mounting bracket at cylinder
head.
Install EGR valve and transfer tube at plenum.
Connect battery.
I NOTE ]APPLY A SMOOTH CONTINUOUS BEAD APPROX
2.0-3.0 WIDE AND 3.0-5.0 THICK ON BOTH SURFACES.
BEAD CONFIGURATION MUST INSURE COMPLETE SEALING
OF WATER AND OIL. SURFACE MUST BE FREE OF OIL AND
DIRT TO INSURE ADEQUATE SEAL.
TORQUE INTAKE MANIFOLD BOLTS
TO
18-34 N.m (1 3-25 FT. LBS.)
841 59
73 2 610 VIEW
Figure 6A2-7 Intake Manifold

2.8 LITER V-6 6A2-9
INTAKE MANIFOLD (FIGURE 6A2-7)
Removal
Disconnect battery.
Remove air cleaner.
Drain coolant.
Refer to Section 6E3 for removal of the following
PFI sub-assemblies.
e Plenum
e Fuel Rail
e Runner
Disconnect spark plug wires at spark plugs.
Disconnect wires at coil.
Remove distributor cap and spark plug wires.
Mark distributor position and remove hold down
bracket.
Remove distributor.
Remove air management hose, manual
transmission only.
Disconnect emission canister hoses. Remove pipe
bracket (front left valve cover).
Remove left valve cover.
Remove air management bracket, manual
transmission only.
Remove right valve cover.
Remove upper radiator hose.
Disconnect heater hose.
Disconnect coolant switches.
Remove manifold bolts.
Remove manifold. Discard manifold gaskets and
remove loose RTV from front and rear ridges of
cylinder case.
Installation
When installing intake gaskets, notice that the
gaskets are marked Right Side and Left Side
(carbureted only). Use them only as indicated to
maintain designed efficiency of this engine.
1. Make
sure that no oil or water is present on
surface when new RTV is applied. Place a 5mm
diameter
(3/16") bead of RTV, # 1052917 or
equivalent, on each ridge.
2. Install
new intake gaskets on cylinder heads.
Hold in place by extending ridge RTV bead up
6mm onto the gasket ends. The new intake
gaskets will have to be cut, where indicated, to
install behind push rods. Cut only those areas
that are necessary.
3. Install intake
manifold on engine. Make sure
areas between case ridges and intake are
completely sealed.
4. Install manifold retaining bolts and nuts and
torque in the sequence shown in Figure 6A2-7.
5. Install heater and radiator hose to manifold.
6. Install rocker covers as previously outlined.
7. Connect coolant switches.
8. Install air management bracket.
9. Install pipe bracket (front left rocker cover).
10. Install distributor, distributor cap and retaining
nut. Do not tighten.
11. Refer to Section 6E3 for installation of PFI
sub-assemblies removed. 12.
Connect
necessary wires and hoses.
13. Fill cooling system with
the proper mixture of
ethylene glycol anti-freeze and water. Do not
install radiator cap.
14. Start
engine, set intitial timing. After set, torque
distibutor hold down clamp bolt to 34
N-m (25
lb. ft.). Recheck timing after torquing bolt.
15. Let engine
run until radiator upper hose becomes
hot (thermostat open).
16. With
engine idling, add coolant to radiator, if
necessary, until level reaches bottom of filler
neck.
17. Install
radiator cap, making sure arrows on cap
line up with overflow tube.
Figure 6A2-8 Exhaust Manifold
EXHAUST MANIFOLD (FIGURE 6A2-8)
Removal (Left)
1. Disconnect battery.
2. Raise vehicle.
3. Disconnect exhaust pipe.
4. Remove
(4) rear manifold bolts and (1) nut.
5. Lower vehicle.
6. Disconnect air management, hoses and wires.
7. Remove power steering and fuel line bracket.
8. Remove manifold.
Installation (Left)
1. Clean mating surfaces on manifold and head,
then install manifold in position and install bolts.
2. Torque
manifold bolts to 34
N.m (25 ft. lbs.).
3. Install power steering bracket.
4. Raise vehicle.
5. Install exhaust pipe.
6. Lower vehicle.
7. Connect battery.
Removal (Right)
1. Disconnect battery.
2. Raise vehicle.
3. Disconnect exhaust pipe.
4. Lower vehicle.