oil dipstick PONTIAC FIERO 1988 Service Repair Manual
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Page 67 of 1825

1B-24 AIR CONDPTIBNING 
EVAPORATOR CORE 
Remove QP Disconnect 
1. Discharge A/C system. 
2. Remove  accumulator. 
3. Remove  two (2) screws  and  remove  hi-blower 
relay  terminal. 
4. Remove  upper  case  screws. 
5. Relocate  wiring  harness  and  remove  dipstick. 
6. Disconnect  liquid  line  fitting. 
7. Remove upper case and  lift evaporator  core  out 
of  case  (retain  foam  wedge). 
Install  or  Connect 
1.  Reverse  removal  procedure  to  reinstall. 
2. Recharge  and  test  system for proper  operation. 
EVAPBRAWORCASE 
Remove  or  Disconnect 
1. Remove  accumulator. 
2. Remove  blower  motor. 
3. Remove  evaporator  core. 
Remove lower case to cowl screws (three driven  from  engine  compartment,  three  driven  from 
interior). 
Remove  case  from cowl. 
Install  or Connect 
Reverse  removal  procedure  to reinstall.  Rein- 
stall  or  replace  gaskets,  seal and sealant 
removed  during  disassembly.  
Recharge  and  test  system  for proper  operation. 
NG COMPRESSOR (TYPICAL) 
Remove or Disconnect 
1. Discharge A/C system. 
2. Remove  fitting  block  (coupled  hose  assembly)  
bolt  at rear  of compressor. 
3. Remove  mounting  bracket bolt(s) . 
4. Remove drive belt (route lower loop behind har-  
monic  balancer  to gain  additional  slack  if 
required). 
5. Remove  compressor. If complete  compressor is 
to  be  replaced,  transfer  usable  switches,  etc. to 
new  compressor. 
Install or Connect 
1.  Reverse  removal 
procedure to  reinstall.  Use 
new  O-rings  lubricated  with 
525 viscosity 
refrigerant  oil. Refer  to Section 
6B for  drive  belt 
tension. 
2. Evacuate  and recharge  system. 
CONDENSER 
a Remove  or Disconnect 
1. Discharge A/C system. 
2. Disconnect coupled hose and liquid line fittings. 
3, Remove  screws  retaining  top  radiator  shield. 
4. Remove  top  condenser  retaining  screws. 
5. Carefully  move  (tilt)  radiator  rearward  and  lift 
condenser  out of radiator  support. 
6. Transfer  brackets and mounts  to new condenser 
if  replacement  is necessary. 
Install  or Connect 
1. Reverse  removal  procedure  to  reinstall. Use 
new  O-rings  lubricated  with 
525 viscosity 
refrigerant  oil. 
2. Recharge  and  test  system  for proper  operation. 
1. HEATER  AND DEFROSTER  ASSEMBLY 
2.  1.4 
N.m (12 LBS. IN.)  INSTALL  FIRST 
3. CONSOLE ASSEMBLY 
4. 
1.4 Narn (12  LBS.  IN.) 
5. FLOOR  OUTLET  ASSEMBLY 
Figure 21 Floor Outlet   
Page 348 of 1825

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.   
Page 363 of 1825

I Liher Body 6 Push Rod Seat Reta~ner 2 Push  Rod Seal 7 Plunger 3 Mater~ng Valve 8 Check  Ball Spr~ng 4 Check  Ball 9 Plunger Spr~ng 5 Check Ball Rete~ner 10 Olllna Flat 
Figure 6A2-14 Valve Lifter 
Disassembly 
1. Hold  the plunger  down  with  a push  rod,  and 
using  the blade  of a small  screw  driver, remove 
the  push  rod  seat  retainer. 
2. Remove the push  rod  seat  and metering  valve. 
3. Remove the plunger,  ball  check  valve  assembly 
and  the plunger  spring. 
4. Remove  the ball check  valve and spring  by prying 
the  ball  retainer  loose from  the plunger  with the 
blade  of a small  screw driver. 
Cleaning  and  Inspection 
Thoroughly  clean  all parts in  cleaning  solvent, 
and  inspect  them carefully.  If  any  parts are damaged 
or  worn,  the entire  lifter  assembly should  be  replaced. 
If  the  lifter  body  wall  is scuffed  or worn,  inspect  the 
cylinder  block lifter bore.  If the  bottom  of the  lifter  is 
scuffed  or worn,  inspect  the camshaft  lobe. If  the push 
rod  seat  is  scuffed  or worn,  inspect  the push  rod.  An 
additive  containing  EP lube,  such as EOS,  should 
always be  added to crankcase  oil for  run-in  when any 
new  camshaft  or lifters  are installed.  All  damaged or 
worn  lifters  should be replaced.  For proper  lifter 
rotation  during  engine operation,  lifter  foot must be 
convex. 
Assembly 
1.  Place 
the check  ball  on  small  hole  in  bottom of 
the  plunger. 
2.  Insert 
check  ball  spring  on seat  in  ball  retainer 
and  place  retainer  over ball  so that  spring  rests on 
the  ball. Carefully press  the retainer  into position 
in plunger  with the blade  of a small screw  driver. 
3. Place the plunger  spring over the ball  retainer  and 
slide  the lifter body  over  the spring  and plunger, 
being  careful  to line  up  the  oil feed  holes  in  the 
lifter  body  and plunger. 
4. Fill the assembly with  SAE 10 oil,  then insert  the 
end  of a 
1/8" drift  pin into  the plunger  and press 
down  solid. Do not attempt  to force  or pump the 
plunger.  At this point,  oil holes in  the lifter body 
and  plunger  assembly  will be  aligned. 
5. Insert  a  1/16" drift pin through both  oil holes to 
hold  the plunger  down against  the lifter  spring 
tension. 
6.  Remove 
the 
1/8" drift pin, refill  assembly  with 
SAE  10 oil. 
7. Install  the metering  valve and push  rod  seat. 
8.  Install the  push rod seat  retainer,  press down  on 
the  push  rod  seat  and remove  the 1/16"  drift  pin 
from  the oil holes.  The lifter  is now  completely 
assembled,  filled with  oil  and ready  for 
installation.  Before installing  lifters,  coat the 
bottom  of the  lifter  with  "Molykote"  or its 
equivalent. 
CYLINDER  HEAD (FIGURE 6A2-15) 
Removal  (Left) 
Remove intake manifold  as previously  outlined. 
Raise  vehicle.  
Drain  engine block. 
Disconnect exhaust  pipe. 
Remove  dipstick tube attachment. 
Lower  vehicle. 
Remove  serpentine  belt. 
Remove  A/C compressor  and lay aside. 
Remove 
P/S pump  and  lay  aside. 
Loosen rocker  arm until  able to remove push  rod. 
Remove  head  bolts. 
Remove  head. 
HEAD TORQUE  SEQUENCE 
/7 , 2 ing. Using a 12" 
Figure 6A2-1'5 Cylinder  Head Installation 
Installation  (Left) 
The gasket  surfaces  on  both head  and cylinder 
case deck  must  be clean  of any foreign  matter and free 
of  nicks  of heavy  scratches. Cylinder  bolt threads  in the 
case  and  threads  on the  cylinder  head  bolts  must  be 
clean.  Dirt will  affect  bolt torque. 
1.  Place  the gasket in  position,  over  the dowel pins, 
with  the note  "This  Side Up"  showing. 
2.  Install  cylinder  head. 
3. Coat cylinder  head  bolt  threads with  sealer, 
#1052080 or equivalent,  and install  bolts.   
Page 364 of 1825

2.8 LITER V.6 6A2.13 
Torque  bolts as shown  in Figure 6A2-15. 
4.  Install 
push  rods  and  loosely retain with  rocker 
arms.  Make  sure lower  ends of 
pushrods are in 
lifter  seats. 
5. Install  intake  manifold. 
6.  Raise  vehicle. 
7.  Install  dipstick  tube  bracket. 
8.  Connect exhaust  pipe 
to exhaust  manifold flange. 
9.  Lower  vehicle. 
10.  Adjust 
valve lash as previously  outlined. 
11.  Continue 
following  intake manifold  installation 
for  build  up. 
Removal  (Right) 
Remove intake manifold  as previously  outlined. 
Raise  vehicle. 
Disconnect  exhaust  pipe. 
Drain  engine block. 
Lower  vehicle. 
Loosen  rocker arms until able to remove  push 
rod.  
Remove  serpentine  belt. 
Remove  tensioner. 
Remove  A.I.R. bracket. 
Remove  generator bracket. 
Remove  head  bolts. 
Remove  head. 
Installation (Right) 
The gasket surfaces  on both the  head and cylinder 
case 
deck must  be clean  of any  foreign  matter and free 
of  nicks  of heavy  scratches. Cylinder  bolt threads  in the 
case  and  threads  on the  cylinder  head  bolts  must be 
clean.  Dirt will affect  bolt torque. 
1.  Place  the gasket in  position,  over  the dowel pins, 
with  the note  "This  Side Up"  showing. 
2.  Install  cylinder  head. 
3. Coat  cylinder  head  bolt threads with  sealer, 
#lo52080 or equivalent,  and  install  bolts. 
Torque  bolts  as shown  in (Figure 
6A2-15). 
Install  push rods and loosely  retain with  rocker 
arms.  Make  sure lower  ends of push  rods are in 
lifter  seats. 
Install  intake  manifold. 
Raise  vehicle. 
Install  exhaust  pipe  to exhaust  manifold  flange. 
Lower  vehicle. 
Adjust  valve lash  as  previously  outlined. 
Install  AIR bracket. 
Install  tensioner. 
Install  generator  bracket. 
Continue  following  intake manifold  installation 
for  build  up. 
Disassembly 
1.  With  cylinder  head  removed,  remove rocker  arm 
nuts,  balls and rocker  arms (if not  previously 
done). 
2.  Using  tool J-8062,  compress  the valve  springs  and 
remove  valve keys.  Release  the compressor  tool  and 
remove  spring caps, oil  shedders, springs  and 
damper  assemblies,  then remove  oil seals. 
3.  Remove  valves from cylinder  head  and place 
them  in a  rack  so  they  can be installed  in their 
original  positions. 
Cleaning and Inspection 
Clean  all carbon  from  combustion  chambers and 
valve  ports using  'tool 
5-8089. 
Thoroughly  clean valve guides  using 5-8 10 1. 
Clean  all  carbon and sludge  from  push  rods, 
rocker  arms and  push  rod  guides. 
Clean  valve stems and  heads on  a buffing  wheel. 
Clean  carbon  deposits  from head  gasket  mating 
surface.  
Inspect  cylinder  head  for cracks in the  exhaust 
ports,  combustion  chambers,  or external  cracks 
to the  water jacket. 
Inspect  the valves  for burned  heads, cracked  faces 
or  damaged  stems. 
NOTICE: Excessive  valve stem to bore  clearance 
will  cause  high  oil consumption  and  may  cause 
valve breakage.  Insufficient clearance  will result  in 
noise  and sticky  functioning  of the  valve  and 
disturb  engine  smoothness. 
8. Measure  valve stem clearance  as  follows: 
a.  Clamp 
a  dial  indicator  on  one  side of the 
cylinder head.  Locate  the  indicator  so that 
movement  of the  valve  stem from  side to 
side (crosswise  to the  head)  will cause direct 
movement  of the  indicator  stem.  The 
indicator  stem must  contact  the side  of the 
valve  stem just  above  the guide. 
b.  Drop 
the valve  head 
1.5mm off the  valve 
seat. 
c.  Move 
the stem  of the  valve  from side  to side, 
using  light  pressure,  to obtain  a  clearance 
reading.  If clearance  exceeds specifications, 
it  will  be necessary to  ream  valve guides for 
oversize valves. Service  valves are available 
in  std.,  089, 
.394 and .775mm O.S. sizes. 
9.  Check 
valve spring  tension  with  tool J-8056, 
spring tester.  Springs should  be compressed  to the 
specified  height  and checked  against  the 
specifications  chart. Springs should be replaced  if 
not  within  44 
N (10 Ibs.) of the  specified  load 
(without  dampers). 
10.  Inspect 
rocker arm studs  for  wear  or damage. 
ROCKER ARM STUDS 
Cylinder  heads  use threaded  rocker arm studs. 
Rocker  arm studs that  have  damaged  threads should 
be  replaced  with  new studs.  If,  for  some  reason,  the 
threads  in the  head 
are damaged  or stripped,  the head 
can  be retapped, and a  helical type insert  added. If such 
an  insert  is not  available,  the head  should  be replaced. 
VALVE GUIDES 
Valves with  oversize stems  are available  in .089, 
,394 and ,775mm over  sizes.  To ream  the valve guide   
Page 380 of 1825

V-8 ENGINE BA3-1 
SECVON 6A3 
TER V8 V N CODE E 
TER V8 V N CODE F 
TER V8 V N CODE 8 
CONTENTS 
GENERAL DESCRIPTION .......................... 6A3- 1 
ENGINE LUBRICATION .......................... 6A3-2 
ON-VEHCILE  SERVICE ............................... 6A3-5 
...................................... Powertrain Mounts 6A3-5 
Intake Manifold ........................................... 6A3-6 
Dipstick  Tube .............................................. 6A3-7 
Exhaust  Manifold ........................................... 6A3-7 
........................................ Rocker Arm Cover 6A3-8 
Rocker  Arm and  Push  Rods ...................... 6A3-8 
Valve Stem  Oil Seal  and/or 
Valve  Spring 
................................................ 6A3-9 
Valve Lifters .................................................. 6A3- 10 
............................. Cylinder Head  Assembly 6A3- 1 1 
...................................... Rocker Arm Studs 6A3- 14 
...................................... Valve  Guide  Bores 6A3- 14 
Valve Seats .................................................. 6A3- 14 
Valves ........................................................... 6A3- 15 
Torsional  Damper ........................................ 6A3- 15 
. 
............................. Crankcase  Front Cover .... 6A3- 1 5 
Oil Seal  (Front  Cover) ................................... 6A3- 16 
Camshaft ...................................................... 6A3- 16 
Camshaft  Bearings ............................. .. ....... 6A3- 17 
Oil Pan ......................................................... 6A3- 18 
..................................................... Oil Pump 6A3- 18 
............................. Connecting  Rod Bearings 6A3- 19 
.............................................. Main  Bearings 6A3-20 
........................................... Rear Main  Seal 6A3-22 
........... Connecting  Rod & Piston Assemblies 6A3-23 
............................................ Cylinder  Block 6A3-26 
............................... Oil Filter  Bypass  Valve 6A3-27 
.......................................... Engine  Assembly 6A3-27 
................................................... Crankshaft 6A3-28 
..................... Sprocket  or Gear  Replacement 6A3-28 
......................................... SPECIFICATIONS 6A3-28 
GENERAL DESCRIPTION 
CYLINDER BLOCK CAMSHAFT  AND DRIVE 
The cylinder  block  is made of cast  iron  and  has  The 
cast iron  camshaft  is supported  by 5 bearings 
8 cylinders  arranged  in  a "V" shape  with 4 cylinders and 
is chain  driven.  A steel  crankshaft  sprocket drives 
in  each bank. 
5 main  bearings  support  the  crankshaft  the 
timing  chain  which  in turn  drives  the camshaft 
which  is  retained  by bearing  caps that are machined through a cast iron 'procket. 
with  the block  for proper  alignment  and clearances. 
Cam lobes  are ground,  hardened  and  tapered 
Cylinders are completely encircled by coolant Jackets, with  the high side toward  the rear. This, cou~led with 
CYLINDER  HEAD a sphericalYface on the  lifter, causes  the "alve lifters to 
rotate. 
Camshaft  bearings  are lubricated  through oil 
The  cast  iron  cylinder  heads  feature individual 
holes which intersect the main oil gallery. The main oil intake and exhaust Ports for each cylinder. Valve gallery is rifle drilled down the center of the block, guides are integral,  and rocker  arms are retained  on above the individual  pressed studs. 
CRANKSHAFT  AND BEARINGS 
The crankshaft  is  cast  nodular iron and is 
supported  by five  main bearings 
#5 is the  end  thrust 
bearing. 
Main bearings  are lubricated  from oil holes which 
intersect  the camshaft bearings.  The camshaft  bearings 
are  fed oil by the  main  oil gallery which  is rifle  drilled 
down  the center  of the  block, above  the camshaft. Two 
additional  oil galleries  are on either  side of the  main  oil 
gallery  to provide  an oil  supply  for the  hydraulic lifters. 
PISTONS  AND CONNECTING  RODS 
The pistons  are made  of cast  aluminum  alloy 
using  two compression rings  and one oil control  ring. 
Piston pins  are offset  1/16" 
(1.6mm) toward  the thrust 
side (right  hand side) to provide  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.   
Page 417 of 1825

6B-8 ENGINE COOLING 
PROBLEMS NOT  REQUIRING  DISASSEMBLY OF COOLING  SYSTEM - 1. LARGE OBSTRUCTIONS  BLOCKING RADIATOR  OR CONDENSER 
a. AUXILIARY  OIL COOLERS 
b. LICENSE  PLATES  R ELOCATE 
c. SPARE  TIRES 
d. ICE, MUD  OR SNOW  OBSTRUCTING  GRILLE - REMOVE 
2. ENGINE OIL OVERFILL - CHECK  ENGINE  OIL DIPSTICK 
3. WRONG  RADIATOR  FOR 
APPLICATION - CHECK  PART NO. AGAINST  PARTS LlST 
4. LOOSE, DAMAGED  OR MISSING  AIR SEALS - SEE  BODY  SERVICE  MANUAL 
5. MISSING OR DAMAGED  LOWER AIR  BAFFLE - SEE BODY  SERVICE  MANUAL 
6. WRONG IGNITION  TIMING - SEE CHASSIS  SERVICE  MANUAL PROBLEMS  REQUIRING  DISASSEMBLY  OF COOLING  SYSTEM - 
1. INCORRECT  OR DAMAGED  FAN - CHECK PART NO. AGAINST  PARTS LlST 
2. FAULTY EMISSION  SYSTEM COMPONENTS  (COULD CAUSE OVERHEATING  AT IDLE) 
; SEE  CHASSIS  SERVICE  MANUAL 
3. PRESSURE  CHECK COOLING  SYSTEM WITH PRESSURE  CAP  INSTALLED - WILL SHOW 
IF  PRESSURE  CAP  LEAKS BECAUSE  OF RADIATOR  FILLER  NECK DAMAGE 
4. DEFECTIVE  WATER PUMP 
a. ERODED  OR BROKEN  IMPELLER  VANES 
b. FAILED  BEARING  OR SEAL - CHECK  FOR SHAFT  OR BEARING PLAY 
5. PLUGGED  RADIATOR  TUBES - SEND TO RADIATOR  REPAIR SHOP FOR FLOW  CHECK 
6. INTERNAL  SYSTEM LEAKS 
B. HEAD GASKET - SEE CHASSIS  SERVICE  MANUAL 
b. CRACKED  BLOCK 
c. TIMING CHAIN COVER 
d. INTAKE  MANIFOLD  GASKET 
7. PLUGGED COOLANT  PASSAGES  IN CYLINDER  HEADS - REMOVE  HEADS  AND CHECK  VISUALLY 
Fig. 6 Cooling System Diagnosis  Chart (3 of 3) 
1. RELIEVE  PRESSURE  AND CAREFULLY  REMOVE RADIATOR  CAP. 
2. RUB W'F. TEMPERATURE STICK* ONTO THERMOSTAT MOUSING. 
3. WARM UP ENGINE  AT FAST  IDLE: 
WATCH  FOR COOLANT  FLOW BEFORE  MAR 
NO COOLANT FLOW INSTALL NEW 
THERMOSTAT. 
COLD ENGINE -SLOW WARMUP -NOT  ENOUGH  HEAT 
1. RELIEVE PRESSURE  AND CAREFULLY  REMOVE RADIATOR  CAP. 
2. RUB 188'~. TEMPERATURE STICK'  ONTO THERMOSTAT HOUSING. 
3. WARM UP ENGINE  AT FAST  IDLE. 
COOLANT FLOW 
- 'NOTE: THE  TEMPERATURE  STICK  IS  A PENCIL LIKE DEVICE  WHICH HAS A WAX  MATERIAL  CONTAINING  CERTAIN CHEMICALS WHICH MELT AT A GIVEN TEMPERATURE THEWERATURE STICKS  CAN BE USED  TO  DETERMINE  A THERMOSTAT'S OPERATING TEMPERATURE  BY RUBBING laB°F AN0 =OF. STICKS ON THE THERMOSTAT HOUSING. THE MARKS MADE BY THE STICKS SHOULD MELT WHEN COOLANT TEMPERATURES OF IWOF'AND W'F. ARE REACHED, RESPECTIVELY. THESE TEMPERATURES ARE THE NORMAL WERATING RANGE OF THE THERMOSTAT. THEREFORE, ~i WE COOLANT  FLOWS AS  INDICATED  ON THE DIAGNOSIS CHART.  THE THERMOSTAT MAY BE DEFECTIVE. 
Fig. 7 Thermostat  Diagnosis  Chart