In front of engine thers a cap like part that has a vaacuum hose coming out of it and connects to exhaust some how

In internal combustion engines,exhaust gas recirculation (EGR) is a nitrogen oxide (NOx) emissions reduction technique used in petrol/gasoline and diesel engines.EGR works by recirculating a portion of an engine's exhaust gas back to the engine cylinders. Thers a hose going down the rear of the engine to the exhaust pipe. It recirculates the portion of the gasses coming out of the engine by putting in back into the intake manifold, where the engine can burn it again, thereby reducing the emissions. The EGR valve is located in the engine compartment (underneath the hood). Usually on the side with the air intake manifold attatched to the side frame rail

Cannister is probably full.

P0171 VOLKSWAGEN - System Too Lean engine cylinder Bank 1
Possible causes- Intake air leaks
- Faulty front heated oxygen sensor
- Ignition misfiring
- Faulty fuel injectors
- Exhaust gas leaks
- Incorrect fuel pressure
- Lack of fuel
- Faulty Mass Air Flow (MAF) sensor
- Incorrect Positive Crankcase Ventilation (PCV) hose connection
P0455 VOLKSWAGEN - EVAP System (fuel vapor storage and control) Large Leak Detected
Possible causes- Missing or loose fuel cap
- Incorrect fuel filler cap used
- Fuel filler cap remains open or fails to close
- Foreign matter caught in fuel filler cap
- EVAP canister or fuel tank leaks
- EVAP system hose leaking
- Fuel tank leaking

Hi, to install follow the procedure below:

1. Install new camshaft seals and retaining plates onto the cylinder. Tighten the right camshaft seal retaining plate 6mm bolts to 65 inch lbs. Tighten the left camshaft seal retaining plate 8mm bolts to 191 inch lbs.
2. Thoroughly clean the cylinder head and engine block sealing surfaces.
3. Place a new head gasket on the engine block and carefully position the cylinder head on top of the new gasket.

Do not reuse or apply oil to the cylinder head bolts.

1. Install new cylinder head bolts and torque them in sequence to 47 ft. lbs. (64 Nm) for the M11 bolts and 15 ft. lbs. (21 Nm) for the M8 bolts.
2. Install the dipstick tube bracket to the cylinder head.
3. Connect the front exhaust pipes to the exhaust manifolds. Tighten the exhaust bolts to 48 ft. lbs. (67 Nm).
4. Install the power steering pump bracket. Torque the mounting bolts to 34 ft. lbs. (46 Nm).
5. Install the cylinder head covers.
6. Install the timing belt and the auto tensioner (pusher). Torque the mounting bolt to 14 ft. lbs. (19 Nm).
7. Install the timing belt cover and oil cooler hoses and bracket.
8. Install the crankshaft pulley. Torque the center bolt to 123 ft. lbs. (167 Nm).
9. Install the fan pulley assembly.
10. Install the power steering pump.
11. Install the accessory drive belts.
12. Install the engine coolant manifold and the heater hose.
13. Install the intake manifold. Torque the nuts and bolts to 17 ft. lbs. (24 Nm) in a crisscross pattern.
14. Install the fuel injector connectors and the fuel hoses to the fuel rail.
15. Install the common chamber. Torque the nuts and bolts to 17 ft. lbs. (24 Nm).
16. Install the EGR valve assembly. Torque the mounting bolts on the valve side to 69 inch lbs. (8 Nm) and the bolts on the exhaust side to 21 ft. lbs. (28 Nm).
17. Connect the evaporative emission canister purge hose.
18. Connect the fuel pressure control valve vacuum hose.
19. Connect the positive crankcase ventilation hose.
20. Install the throttle body assembly. Torque the mounting bolts to 14 ft. lbs. (19 Nm).
21. Connect the vacuum hoses to the throttle body.
22. Install the ignition control module and the spark plug wires.
23. Connect the MAP sensor; Canister vacuum switching valve (VSV); Exhaust gas recirculation (VSV); Intake air temperature sensor and ground connectors.
24. Connect the vacuum booster hose.
25. Connect the air vacuum hose.
26. Connect the accelerator cable. Adjust the accelerator cable by pulling the cable housing while closing the throttle valve and tightening the adjusting nut and screw cap by hand temporarily. Now loosen the adjusting nut by three turns and then tightening the screw cap. Make sure the throttle valve reaches the screw stop when the throttle is closed.
27. Install the cooling fan assembly and the upper fan shroud.
28. Install the air cleaner assembly.
29. Connect the negative battery cable.
30. Refill and bleed the cooling system.
31. Refill and bleed the power steering pump if necessary.
32. Refill the engine with fresh oil.
33. Run the engine and check for leaks and proper compression.

Best of luck............

To install:

1. Install new camshaft seals and retaining plates onto the cylinder. Tighten the right camshaft seal retaining plate 6mm bolts to 65 inch lbs. Tighten the left camshaft seal retaining plate 8mm bolts to 191 inch lbs.
2. Thoroughly clean the cylinder head and engine block sealing surfaces.
3. Place a new head gasket on the engine block and carefully position the cylinder head on top of the new gasket.

Do not reuse or apply oil to the cylinder head bolts.

1. Install new cylinder head bolts and torque them in sequence to 47 ft. lbs. (64 Nm) for the M11 bolts and 15 ft. lbs. (21 Nm) for the M8 bolts.
2. Install the dipstick tube bracket to the cylinder head.
3. Connect the front exhaust pipes to the exhaust manifolds. Tighten the exhaust bolts to 48 ft. lbs. (67 Nm).
4. Install the power steering pump bracket. Torque the mounting bolts to 34 ft. lbs. (46 Nm).
5. Install the cylinder head covers.
6. Install the timing belt and the auto tensioner (pusher). Torque the mounting bolt to 14 ft. lbs. (19 Nm).
7. Install the timing belt cover and oil cooler hoses and bracket.
8. Install the crankshaft pulley. Torque the center bolt to 123 ft. lbs. (167 Nm).
9. Install the fan pulley assembly.
10. Install the power steering pump.
11. Install the accessory drive belts.
12. Install the engine coolant manifold and the heater hose.
13. Install the intake manifold. Torque the nuts and bolts to 17 ft. lbs. (24 Nm) in a crisscross pattern.
14. Install the fuel injector connectors and the fuel hoses to the fuel rail.
15. Install the common chamber. Torque the nuts and bolts to 17 ft. lbs. (24 Nm).
16. Install the EGR valve assembly. Torque the mounting bolts on the valve side to 69 inch lbs. (8 Nm) and the bolts on the exhaust side to 21 ft. lbs. (28 Nm).
17. Connect the evaporative emission canister purge hose.
18. Connect the fuel pressure control valve vacuum hose.
19. Connect the positive crankcase ventilation hose.
20. Install the throttle body assembly. Torque the mounting bolts to 14 ft. lbs. (19 Nm).
21. Connect the vacuum hoses to the throttle body.
22. Install the ignition control module and the spark plug wires.
23. Connect the MAP sensor; Canister vacuum switching valve (VSV); Exhaust gas recirculation (VSV); Intake air temperature sensor and ground connectors.
24. Connect the vacuum booster hose.
25. Connect the air vacuum hose.
26. Connect the accelerator cable. Adjust the accelerator cable by pulling the cable housing while closing the throttle valve and tightening the adjusting nut and screw cap by hand temporarily. Now loosen the adjusting nut by three turns and then tightening the screw cap. Make sure the throttle valve reaches the screw stop when the throttle is closed.
27. Install the cooling fan assembly and the upper fan shroud.
28. Install the air cleaner assembly.
29. Connect the negative battery cable.
30. Refill and bleed the cooling system.
31. Refill and bleed the power steering pump if necessary.
32. Refill the engine with fresh oil.
33. Run the engine and check for leaks and proper compression.

Water Pump REMOVAL & INSTALLATION CAUTION
Never open, service or drain the radiator or cooling system when hot; serious burns can occur from the steam and hot coolant. Also, when draining engine coolant, keep in mind that cats and dogs are attracted to ethylene glycol antifreeze and could drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantities. Always drain coolant into a sealable container. Coolant should be reused unless it is contaminated or is several years old. 2.4L Engine

1. Disconnect the negative battery cable
2. Detach the Oxygen (O2) sensor electrical connector.
3. Properly drain the engine coolant into a suitable container. Remove the heater hose from the thermostat housing for a more complete coolant drain.
4. Remove upper exhaust manifold heat shield.
5. Remove the bolt that attaches the exhaust manifold brace to the manifold.
6. Remove the lower exhaust manifold heat shield.
7. Break the manifold-to-exhaust pipe spring loaded bolts loose using a 13mm box wrench.
8. Raise and safely support the vehicle. NOTE: It is necessary to relieve the spring pressure from 1 bolt prior to removing the second bolt. If the spring pressure is not relieved, it will cause the exhaust pipe to twist and bind up the bolt as it is removed.
   
9. Unfasten the two radiator outlet pipe-to-water pump cover bolts.
10. Remove the manifold to exhaust pipe bolts from the exhaust pipe flange as follows:
    1. Unscrew either bolt clockwise 4 turns.
    2. Remove the other bolt.
    3. Remove the first bolt. NOTE: DO NOT rotate the flex coupling more than 4°or damage may occur.
       
11. Pull down and back on the exhaust pipe to disengage it from the exhaust manifold bolts.
12. Remove the radiator outlet pipe from the oil pan and transaxle. Leave the lower radiator hose attached and pull down on the outlet pipe to remove it from the water pump. Leave the radiator outlet pipe hang.
13. Carefully lower the vehicle.
14. Unfasten the exhaust manifold-to-cylinder head retaining nuts, then remove the exhaust manifold, seals and gaskets.
15. Remove the front timing chain cover and the chain tensioner. For details, please refer to the procedure located later in this section.
16. Unfasten the water pump-to-cylinder block bolts. Remove the water pump-to-timing chain housing nuts. Remove the water pump and cover mounting bolts and nuts. Remove the water pump and cover as an assembly, then separate the two pieces. Fig. 1: Water pump and cover mounting - 2.4L engine
    To install:
    
17. Thoroughly clean and dry all mounting surfaces, bolts and bolt holes. Using a new gasket, install the water pump to the cover and tighten the bolts finger-tight.
18. Lubricate the splines of the water pump with clean grease and install the assembly to the engine using new gaskets. Install the mounting bolts and nuts finger-tight.
19. Lubricate the radiator outlet pipe O-ring with antifreeze and slide the pipe onto the water pump cover. Install the bolts finger-tight.
20. With all gaps closed, tighten the bolts, in the following sequence, to the proper values:
    1. Pump assembly-to-chain housing nuts:19 ft. lbs. (26 Nm).
    2. Pump cover-to-pump assembly: 106 inch lbs. (12 Nm).
    3. Cover-to-block, bottom bolt first: 19 ft. lbs. (26 Nm).
    4. Radiator outlet pipe assembly-to-pump cover: 125 inch lbs. (14 Nm).
21. Using new gaskets, install the exhaust manifold. Make sure to following the tightening sequence and torque specifications given in the exhaust manifold procedure located in this section.
22. Raise and safely support the vehicle.
23. Index the exhaust manifold bolts into the exhaust pipe flange.
24. Connect the exhaust pipe to the manifold. Install the exhaust pipe flange bolts evenly and gradually to avoid binding. Turn the bolts in until fully seated.
25. Connect the radiator outlet pipe to the transaxle and oil pan.
26. Install the timing chain tensioner and front cover.
27. Install the lower heat shield.
28. Carefully lower the vehicle.
29. Fasten the bolt that attaches the exhaust manifold brace to the manifold.
30. Tighten the manifold-to-exhaust pipe nuts to specification.
31. Install the upper heat shield.
32. Attach the oxygen sensor connector.
33. Fill the radiator with coolant until it comes out the heater hose outlet at the thermostat housing. Then connect the heater hose. Leave the radiator cap off.
34. Connect the negative battery cable, then start the engine. Run the vehicle until the thermostat opens, fill the radiator and recovery tank to their proper levels, then turn the engine OFF.
35. Once the vehicle has cooled, recheck the coolant level, then install the radiator cap.

A.I.R. emissions consist of a belt driven air pump some valves, and a pipe connection to the exhaust manifold. this connection is under the intake mainifold and may be seen by looking above the top of the front tire with the car jacked up and or the wheel removed with the cover pushed back to see the engine. ther can be an emmissions sticker under the hood that shows where the hoses hook to. theres supposed to be one but they fall off and are required in the U.S. but may not in other countries.

2.4L Engine

1. Disconnect the negative battery cable
   
2. Detach the Oxygen (O2) sensor electrical connector.
   
3. Properly drain the engine coolant into a suitable container. Remove the heater hose from the thermostat housing for a more complete coolant drain.
   
4. Remove upper exhaust manifold heat shield.
   
5. Remove the bolt that attaches the exhaust manifold brace to the manifold.
   
6. Remove the lower exhaust manifold heat shield.
   
7. Break the manifold-to-exhaust pipe spring loaded bolts loose using a 13mm box wrench.
   
8. Raise and safely support the vehicle.
   

NOTE It is necessary to relieve the spring pressure from 1 bolt prior to removing the second bolt. If the spring pressure is not relieved, it will cause the exhaust pipe to twist and bind up the bolt as it is removed.

1. Unfasten the two radiator outlet pipe-to-water pump cover bolts.
   
2. Remove the manifold to exhaust pipe bolts from the exhaust pipe flange as follows:
   
   1. Unscrew either bolt clockwise 4 turns.
      
   2. Remove the other bolt.
      
   3. Remove the first bolt.
      

NOTE DO NOT rotate the flex coupling more than 4° or damage may occur.

1. Pull down and back on the exhaust pipe to disengage it from the exhaust manifold bolts.
   
2. Remove the radiator outlet pipe from the oil pan and transaxle. Leave the lower radiator hose attached and pull down on the outlet pipe to remove it from the water pump. Leave the radiator outlet pipe hang.
   
3. Carefully lower the vehicle.
   
4. Unfasten the exhaust manifold-to-cylinder head retaining nuts, then remove the exhaust manifold, seals and gaskets.
   
5. Remove the front timing chain cover and the chain tensioner. For details, please refer to the procedure located later in this section.
   
6. Unfasten the water pump-to-cylinder block bolts. Remove the water pump-to-timing chain housing nuts. Remove the water pump and cover mounting bolts and nuts. Remove the water pump and cover as an assembly, then separate the two pieces.
   

Water pump and cover mounting—2.4L engine
Click to Enlarge To install:

1. Thoroughly clean and dry all mounting surfaces, bolts and bolt holes. Using a new gasket, install the water pump to the cover and tighten the bolts finger-tight.
   
2. Lubricate the splines of the water pump with clean grease and install the assembly to the engine using new gaskets. Install the mounting bolts and nuts finger-tight.
   
3. Lubricate the radiator outlet pipe O-ring with antifreeze and slide the pipe onto the water pump cover. Install the bolts finger-tight.
   
4. With all gaps closed, tighten the bolts, in the following sequence, to the proper values:
   
   1. Pump assembly-to-chain housing nuts:19 ft. lbs. (26 Nm).
      
   2. Pump cover-to-pump assembly: 106 inch lbs. (12 Nm).
      
   3. Cover-to-block, bottom bolt first: 19 ft. lbs. (26 Nm).
      
   4. Radiator outlet pipe assembly-to-pump cover: 125 inch lbs. (14 Nm).
      
5. Using new gaskets, install the exhaust manifold. Make sure to following the tightening sequence and torque specifications given in the exhaust manifold procedure located in this section.
   
6. Raise and safely support the vehicle.
   
7. Index the exhaust manifold bolts into the exhaust pipe flange.
   
8. Connect the exhaust pipe to the manifold. Install the exhaust pipe flange bolts evenly and gradually to avoid binding. Turn the bolts in until fully seated.
   
9. Connect the radiator outlet pipe to the transaxle and oil pan.
   
10. Install the timing chain tensioner and front cover.
    
11. Install the lower heat shield.
    
12. Carefully lower the vehicle.
    
13. Fasten the bolt that attaches the exhaust manifold brace to the manifold.
    
14. Tighten the manifold-to-exhaust pipe nuts to specification.
    
15. Install the upper heat shield.
    
16. Attach the oxygen sensor connector.
    
17. Fill the radiator with coolant until it comes out the heater hose outlet at the thermostat housing. Then connect the heater hose. Leave the radiator cap off.
    
18. Connect the negative battery cable, then start the engine. Run the vehicle until the thermostat opens, fill the radiator and recovery tank to their proper levels, then turn the engine OFF.
    
19. Once the vehicle has cooled, recheck the coolant level, then install the radiator cap.
    

3.1L Engine

1. Disconnect the negative battery cable.
   
2. Properly drain the cooling system into a suitable container.
   
3. Loosen, but do not remove, the water pump pulley bolts.
   
4. Remove the serpentine belt.
   
5. Unfasten the water pump pulley bolts, then remove the pulley.
   
6. Remove the five water pump mounting bolts, then remove the water pump.
   

To install:
View of the water pump mounting and bolt tightening specifications—3.1L engine shown
Click to Enlarge

1. Clean all the gasket surfaces completely.
   
2. Apply a thin bead of sealer around the outside edge of the water pump along the gasket sealing area, then install the gasket onto the water pump.
   
3. Position the water pump on the engine, then tighten the water pump mounting bolts to 89 inch lbs. (10 Nm).
   
4. Install the water pump pulley and finger-tighten the pulley bolts.
   
5. Install the serpentine belt.
   
6. Tighten the water pump pulley bolts to 18 ft. lbs. (25 Nm).
   
7. Fill the cooling system.
   
8. Connect the negative battery cable, then start the engine. Let the engine run until it reaches normal operating temperature, then check for leaks and coolant level. Add coolant, if necessary, then turn the engine OFF.
   

If your shure that a hose is on wrong then there is a place it goesonto that is also wrong . Two wromgs. The only place that a hse could be on wrong is at the exhaust asperater tube that hooks the EGR vavle to the exaust manifold. The heater hoses hook next to each other behind the engine going though the firewall. Follow these hoses back to the motor and see that they don't connect to the pipe on the lower left side of the exaust manifold. If its doing that remove it and see if you can find another hose the same size that will reach the exhaust tube and connect it and vise versa connect the other hose there. The Hoses can be alright though and the engine has a bigger problem a blown head gasket or cracked head. On some models the catalist converter has a hose hooked to it remove it and see itf water comes out, if shouldn't but if it does follow it back to the engine and unhook it there. If water ( Coolant comes out ) ( You may Have to add coolant not water to the cooling system to tell ) then this connection should be connected to a heater hose that you found going thogh the firwall. If you still dont find the problem and the cooling system holds presure and the water coming out the tailpipe is coolant and the engine runs OK ( I dought it). All engines produce a little water when running mainly when run shortly and not warmed up, it will appear black in color and not smell like antifreze. A prankster could have put the garden hose or man hose up the tailpipe to worry you some suspect those that helped point out the water in the first place. The exhaust hoses hook up to the air cleaner housing and pipe and the water hoses hook to the firewall a pipe on the back of the block and a short pipe hooked to the water pump. Repair manuels have pictures of the hoeses in the cooling system chapters.

The code PO420 you have is Catalyst System efficiency is below threshold bank one. Usually replacing the O2 sensor that's the front most in the exhaust system will cure your problem, Your Check Engine light is on and you find a P0420 code for a catalytic converter fault. Does that really mean your converter has reached the end of the road and needs to be replaced? A new converter can cost $600 to $1000 or more if a new car dealer or repair shop does the job, or maybe half that amount if you do it yourself. It's an expensive fix that may or may not be necessary. The problem, in most cases, is an emissions issue, not a performance issue that affects the way the engine runs.
A P0420 diagnostic trouble code is a "generic" fault code that is set when the Onboard Diagnostic II (OBD II) system sees a drop in converter efficiency. The OBD II system monitors catalyst efficiency by comparing the switching activity of the upstream and downstream oxygen sensors in the exhaust. The upstream O2 sensor in theexhaust manifold reflects the condition of the exhaust gases as they exit the engine. The downstream O2 sensor in or behind the catalytic converter reflects the condition of the exhaust after it passes through he converter.
The catalytic converter is like an after-burner. It oxidizes (burns) any residual fuel vapors (unburned hydrocarbons or HC) in the exhaust. It also burns any carbon monoxide (CO) in the exhaust. The exhaust must meet federal emission standards, and if a problem exists that causes emissions to exceed the federal limits by 150%, the OBD II system is supposed to catch the fault, set a code and turn on the Check Engine light.
Thanks.