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For addit ional information, refer t o: Elect ronic Engine Cont rols (303-14A Elect ronic Engine Controls - I6 3.2L Pet rol, Des cript ion andOperation).
Variable Camshaft Timing Solenoid and Camshaft Position Sensors
ItemPart NumberDescription1-CMP Sens or - exhaus t cams haft2-VCT s olenoid3-CMP Sens or - intake camshaftThe profile, or pos ition and shape of the cams haft lobes are opt imiz ed for a cert ain engine rpm, but this normally limit s low-endtorque or high-end power. At high engine s peeds , an engine requires large amounts of air. However, t he intake valves may clos ebefore all t he air has been given a chance t o flow in. On t he other hand, if the cams haft keeps t he valves open for longer periodsof time, problems st art t o occur at t he lower engine speeds . This will caus e unburnt fuel t o exit t he engine s ince t he valves arest ill open.
To overcome t his , VCT changes t he valve t iming by eit her advancing or ret arding the cams haft s t o allow for opt imum engineperformance, reduced emis s ions, and increased fuel efficiency. This is achieved via an electronically controlled hydraulic s olenoidvalve locat ed in t he camshaft housing at t he rear of t he engine, behind the rear CPS s olenoid. The ECM t rans mit s a signal t o thesolenoid, which direct s engine oil int o t he VCT unit. A valve s pool in the VCT unit regulat es t he flow of oil.For addit ional information, refer t o: Elect ronic Engine Cont rols (303-14A Elect ronic Engine Controls - I6 3.2L Pet rol, Des cript ion andOperation)..
There are 2 CMP s ens ors locat ed in t he camshaft housing. The CMP s ensors monitor the posit ion of the cams haft s t o est ablis hignit ion t iming order, fuel injection t riggering and for accurate VCT cams haft advance-retard t iming feedback.
The CMP sensor is a Hall-effect s ens or, which s wit ches a batt ery fed supply on and off. The s upply is s wit ched when t he t eet h ofthe reluct or pas s by t he tip of t he sens or. The 4 t eet h are of differing s hapes , s o the ECM can determine t he exact pos it ion of t hecams haft at any t ime.For addit ional information, refer t o: Elect ronic Engine Cont rols (303-14A Elect ronic Engine Controls - I6 3.2L Pet rol, Des cript ion andOperation).
Spark Plugs
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ItemPart NumberDescription1-Spark plug (6 of)The s park plugs s crew into t he cylinder head t hrough the cams haft hous ing and are controlled by the ECM via individual coils .
Ignition Coils
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ItemPart NumberDescription1-Ignition coil (6 off)The ECM us es a s eparat e ignit ion coil for each spark plug. The ignit ion coils are of t he plug t op des ign, which at t ach t o t he t op ofthe s park plug. The coils are s ecured to the cams haft hous ing wit h a bolt.
The coil has a rubber seal, which s eals t he coil in the s park plug hole in t he cylinder head, prevent ing t he ingres s of mois t ure anddebris around t he spark plug. Thes e coils eliminat e t he requirement for HT leads , which in turn improves t he ignition s ys t emreliabilit y.
Each coil has a 3-pin female connect or, which provide for a bat tery volt age ignit ion feed, an eart h for t he s econdary winding and aprimary winding negat ive (s wit ch) terminal. The s wit ch t erminal of each coil is connect ed t o a separat e pin on t he ECM to allowindependent s wit ching.For addit ional information, refer t o: Elect ronic Engine Cont rols (303-14A Elect ronic Engine Controls - I6 3.2L Pet rol, Des cript ion andOperation).
Fuel Rail and Injectors
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ItemPart NumberDescription1-Fuel rail2-Fuel rail pres s ure and t emperat ure sensor3-Fuel pres s ure pipeThe fuel rail maint ains a fuel pres sure of 3.8 bar (55 ps i) above manifold depres s ion under normal operat ing condit ions , t houghthis is programmed t o ris e t o 4.2 bar (61 ps i) in res pons e t o either:
Cold st art condit ions , t o improve fuel vaporiz ationCold fuel conditions , as the colder t he fuel t he higher vis cos it y
The fuel rail is at t ached to t he int ake s ide of t he cylinder head with 3 bolt s . Six fuel inject ors are inst alled in the cylinder headand connect ed to t he fuel rail. 'O' ring s eals are used t o seal t he inject ors in both t he fuel rail and cylinder head. A connection forthe fuel pres sure pipe is locat ed bet ween injectors 1 and 2.
There is a fuel rail press ure and t emperature s ens or located at t he end of t he fuel rail, next t o injector number 6. The press uresens or cont inuous ly monitors t he fuel pres s ure in the fuel rail, t his value is us ed by the ECM t o calculat e t he inject or puls e-widt hrequired to deliver the correct mas s of fuel per inject ion. The t emperat ure sensor meas ures t he t emperat ure of t he fuel in the fuelrail. This input is t hen us ed to deliver t he correct quant ity of fuel to the engine.For addit ional information, refer t o: Elect ronic Engine Cont rols (303-14A Elect ronic Engine Controls - I6 3.2L Pet rol, Des cript ion andOperation).
Vacuum Pump
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ItemPart NumberDescription1-Vacuum pumpThe intake camshaft is equipped wit h t he VCT unit. The int ake cams haft also drives the vacuum pump.
• NOTE: W hen ins t alling the vacuum pump make sure t he s lot in the VCT unit and t he vacuum pump coupling are in t he vert icalposit ion t o aid ins t allat ion. The vert ical pos it ion is marked on the vacuum pump housing by 2 raised lines .
Intake Manifold
ItemPart NumberDescription1-Int ake manifold2-Variable plenum valve3-Bolt (7 of)4-Throt t le body and module
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5-Bolt (2 of)6-Variable tract valveThe intake manifold att aches t o t he cylinder head wit h 6 bolt s and t he oil pan with 2 bolt s .
The manifold is capable of varying both int ake tract length and plenum volume by means of 2 separat e valves .
At low engine s peeds , long int ake tract s are ut iliz ed to provide opt imum engine t orque. Short er t racts are us ed at medium s peeds ,again, t o optimiz e engine t orque for t he exist ing engine s peed range.
At higher engine s peeds the benefit s of opt imizing t he t ract lengt hs are outweighed by the necess it y of maintaining anappropriate supply of air to meet t he engines requirement s . Therefore, t he plenum valve is opened t o create a s ingle, largeplenum volume to provide t he maximum quant ity of air t o charge the engines cylinders.For addit ional information, refer t o: Int ake Air Dis tribut ion and Filtering (303-12A Int ake Air Dis t ribution and Filt ering - I6 3.2LPet rol, Des cript ion and O perat ion).
Exhaust Manifold
ItemPart NumberDescription1-Exhaus t manifold as sembly2-Gas ket3-Exhaus t manifold - cylinders 1 t o 34-Exhaus t manifold - cylinders 4 t o 6The exhaus t manifold compris es 2 s eparat e manifold as semblies . One manifold is us ed for cylinders 1 t o 3 and t he secondmanifold is us ed for cylinders 4 t o 6. The manifolds are sealed t o the cylinder head wit h a gas ket and s ecured with 14 bolts .
Each manifold comprises 3 fabricat ed branches , which merge int o an int egral cat alyt ic convert er. A t hreaded bos s is posit ionedwhere t he 3 branches merge and provides for t he fit ment of a pre-catalyst Heat ed O xygen Sens or (HO2S). The cat alyt ic convert erout let s have offset flanges which mat e wit h corresponding flanges on t he front s ect ion exhaust s ys t em.
A bracket on each out let flange allows for t he at t achment of an exhaus t manifold heat shield.
CRANKSHAFT, BEDPLATE AND OIL PAN COMPONENTS
The crankshaft and oil pan components are:
Cranks haft and main bearingsCranks haft vibrat ion damper and cooling valveBedplat eO il filter and cooler ass emblyO il pump ass emblyO il pick-upO il panO il level gageSt art er mot or
Crankshaft and Main Bearings
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ItemPart NumberDescriptionA-Thrus t bearing - posit ion 6B-Grooved main bearing - pos it ions 2, 3 and 5C-Main bearing - pos it ions 1, 4 and 7
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The crankshaft is made of forged s teel and has induction hardened bearing s urfaces . There are 2 types of aluminium main bearing:
W it h complet e oil duct s for upper main bearings 2, 3, 5 and 6W it h short oil ducts for all lower and 1, 4 and 7 upper main bearings
Due t o mis s ing count er-weight s for cylinders 1 and 6 and s elected count er-balancing of the entire crankshaft , main bearings 1, 4and 7 are exposed t o great er loads t han the ot hers. To reduce t he load on the bearings , bearing shells wit h s hort oil duct s areus ed. In addit ion, these main bearings have t heir own oil circuit where t he oil is not dis tribut ed on t o t he connecting rod bearings.The 6t h main bearing als o works as a t hrus t bearing.
A gear wheel is crimped to t he rear edge of the crankshaft . The gear wheel drives t he oil pump and the Rear End Ancillary Drive(READ) t iming gear.
The crankshaft has a vis cous vibration damper locat ed directly in front of t he connecting rod pin for cylinder 1, i.e. located in theact ual cylinder block.
Crankshaft Vibration Damper and Cooling Valve