The PCV system controls which exhaust emission(s)?

Exhaust gas recirculation (EGR) is generally not needed under all the following conditions EXCEPT ____________.

Cruise Speed

here is the output of the AIR pump directed when the engine is cold?

Exhaust Manifold

1. Know how PCV systems can be tested

Rattle, 3x5 test, Water monometer

1. Know what too much negative pressure can cause.

Rough idle ,Stalling

An EGR valve that is partially stuck open would MOST likely cause what condition?

Rough idle/stalling

1. Know the normal behavior of PCV at idle and under load.

Slightly negative

1. Know the various ways to lower combustion temperatures

Riching the air flow ratio, Increase Valve overlap

When checking for the proper operation of the AIR system using an exhaust gas analyzer, how much should the oxygen (02) levels increase when the pump is allowed to function?

1 to 4%

When testing an EGR system for proper operation using a vacuum gauge, how much should the vacuum drop when the EGR is commanded ON by a scan tool?

6 to 8 in. Hg

Know what happens to O2 levels when EGR applied

Above 400 MV rich but still Lean

Know what can cause too much positive pressure

Bad piston Rings, Closed PCV

A P0401 DTC (exhaust gas recirculation flow insufficient) is being discussed. Technician A says that a defective EGR valve could be the cause. Technician B says that clogged EGR passages could be the cause. Which technician is correct?

Both A and B

OBD II regulations require that the EGR system be tested. Technician A says that the PCM can monitor the commanded position of the EGR valve to determine if it is functioning correctly. Technician B says that the PCM can open the EGR valve and monitor for a change in the MAP sensor or oxygen sensor reading to detect if the system is functioning correctly. Which technician is correct?

Both A and B

Technician A says that a low-restriction exhaust system could prevent a back pressure-type vacuum controlled EGR valve from opening correctly. Technician B says restricted exhaust can cause the EGR valve position sensor to fail. Which technician is correct?

Both A and B

Two technicians are discussing clogged EGR passages. Technician A says clogged EGR passages can cause excessive NOx exhaust emissions. Technician B says that clogged EGR passages can cause the engine to ping (spark knock or detonation). Which technician is correct? A only

Both A and B

The PCV system controls which exhaust emission(s)?

Both HC and CO

The SAI system is used to reduce which exhaust emission(s)?

Both HC and CO

Know how combustion burn rate and ignition timing are affected when EGR is applied

Burn rate Slows Down

Know what the effect of adding EGR has on fuel trim.

Fuel Trim Goes Negative

1. Know what emissions SAI is supposed to help reduce.

Hc and Co

What causes the nitrogen and the oxygen in the air to combine and form NOx?

Heat above 2500 degrees F

1. Know what conditions have to be true in order for EGR to be enabled

Hot and not Idle

1. Know what happens to MAP (kpa) and Manifold Vacuum when EGR is applied

MAP Increases Vacuum Decreases

1. Know the different methods of monitoring EGR activity

MAP,DELTA,EGR,PKAP,RPM

1. Know how Orifice type works

No moving parts

1. Know what too much positive pressure can cause

Oil leaks

EGR is used to control which exhaust emission?

Oxides of nitrogen (NOx)

PCV

Positive Crankcase Ventilation

A typical EGR pintle-position sensor is what type of sensor?

Potentiometer

The switching valves on the AIR pump have failed several times. Technician A says that a defective exhaust check valve could be the cause. Technician B says that a leaking exhaust system at the muffler could be the cause. Which technician is correct?

Technician A only

Technician A says that if a PCV valve rattles, then it is okay and does not need to be replaced. Technician B says that if a PCV valve does not rattle, it should be replaced. Which technician is correct?

Technician B only

Technician A says that the PCV system should create a slight pressure in the crankcase at idle. Technician B says that the PCV system should create a slight vacuum in the crankcase at 2,500 RPM. Which technician is correct?

Technician B only

Two technicians are discussing exhaust check valves used in SAI systems. Technician A says that they are used to prevent the output from the SAI pump from entering the intake manifold. Technician B says the check valves are used to keep the exhaust from entering the AIR pump. Which technician is correct?

Technician B only

How much of the air needed by the engine flows through the PCV system when the engine is at idle speed?

Up to 30%

1. Know what can cause too much negative pressure

clogged air filter

1. Know what an improperly functioning EGR will cause.

valve stuck open, poor idle, knocking producing, more NOx