Mazda Speed 6. Manual — part 6

01 ENGINE

26

Turbocharger Diagnosis

Black Smoke

Dirty air fi lter system
Suction and pressure line distorted or leaking
Excessive fl ow resistance in exhaust system/leakage
upstream of turbine
Fuel system/injection feed system defective or incorrectly
adjusted
Valve guide, piston rings, engine or cylinder liners worn/
increased blow by
Dirty compressor or charge air cooler
Boost pressure control swing valve/poppet valve does not
close
Turbocharger bearing damage
Foreign body damage on compressor or turbine
Engine air collector cracked/missing or loose gaskets
Turbine housing/fl ap damaged
Insuffi cient oil supply of turbocharger

Lack of Power/Boost Pressure Low

Dirty air fi lter system
Suction and pressure line distorted or leaking
Excessive fl ow resistance in exhaust system/ leakage
upstream of turbine
Fuel system/injection feed system defective or incorrectly
adjusted
Valve guide, piston rings, engine or cylinder liners worn/
increased blow by
Dirty compressor or charge air cooler
Boost pressure control swing valve/poppet valve does not
close
Pipe assy. to swing valve/poppet valve defective
Turbocharger bearing damage
Foreign body damage on compressor or turbine
Engine air collector cracked/missing or loose gaskets
Turbine housing/fl ap damaged
Insuffi cient oil supply of turbocharger

Boost Pressure Too High

Fuel system/injection feed system defective or incorrectly
adjusted
Boost pressure control swing valve/poppet valve does not
open
Pipe assy. to swing valve/poppet valve defective

Compressor/Turbine Wheel Failure

Turbocharger bearing damage
Foreign body damage on compressor or turbine
Turbine housing/fl ap damaged
Insuffi cient oil supply of turbocharger

High Oil Consumption

Dirty air fi lter system
Excessive fl ow resistance in exhaust system/ leakage
upstream of turbine
Oil feed and drain lines clogged, leaking or distorted
Crankcase ventilation clogged and distorted
Coke and sludge in turbocharger center housing
Valve guide, piston rings, engine or cylinder liners worn/
increased blow by
Dirty compressor or charge air cooler
Piston ring sealing defective
Turbocharger bearing damage

Blue Smoke

Dirty air fi lter system
Excessive fl ow resistance in exhaust system/ leakage
upstream of turbine
Oil feed and drain lines clogged, leaking or distorted
Crankcase ventilation clogged and distorted
Coke and sludge in turbocharger center housing
Valve guide, piston rings, engine or cylinder liners worn/
increased blow by
Dirty compressor or charge air cooler
Piston ring sealing defective
Turbocharger bearing damage

Black and Blue Smoke

Dirty air fi lter system
Excessive fl ow resistance in exhaust system/ leakage
upstream of turbine
Valve guide, piston rings, engine or cylinder liners worn/
increased blow by
Dirty compressor or charge air cooler
Turbocharger bearing damage

Oil Leakage at Turbine

Oil feed and drain lines clogged, leaking or distorted
Crankcase ventilation clogged and distorted
Coke and sludge in turbocharger center housing
Valve guide, piston rings, engine or cylinder liners worn/
increased blow by
Piston ring sealing defective
Turbocharger bearing damage

Turbocharger noise

Suction and pressure line distorted or leaking
Excessive fl ow resistance in exhaust system/ leakage
upstream of turbine
Dirty compressor or charge air cooler
Turbocharger bearing damage
Foreign body damage on compressor or turbine
Exhaust gas leakage between turbine outlet and exhaust
pipe
Engine air collector cracked/missing or loose gaskets
Turbine housing/fl ap damaged
Insuffi cient oil supply of turbocharger

Oil Leakage at Compressor

Dirty air fi lter system
Excessive fl ow resistance in exhaust system/ leakage
upstream of turbine
Oil feed and drain lines clogged, leaking or distorted
Crankcase ventilation clogged and distorted
Coke and sludge in turbocharger center housing
Valve guide, piston rings, engine or cylinder liners worn/
increased blow by
Dirty compressor or charge air cooler
Piston ring sealing defective
Turbocharger bearing damage

01 ENGINE

27

Black
Blue Smoke
Compressor/Turbine Wheel Failure

Turbocharger bearing damage

Black
Blue Smoke
High Oil Consumption
Compressor/Turbine Wheel Failure

Turbocharger bearing damage

Black
Blue Smoke
High Oil Consumption

Dirty air fi lter system
Excessive fl ow resistance in exhaust system/ leakage
upstream of turbine
Valve guide, piston rings, engine or cylinder liners worn/
increased blow by
Dirty compressor or charge air cooler
Turbocharger bearing damage

Black
Blue Smoke
Insuffi cient power

Dirty air fi lter system
Excessive fl ow resistance in exhaust system/ leakage
upstream of turbine
Valve guide, piston rings, engine or cylinder liners worn/
increased blow by
Dirty compressor or charge air cooler
Turbocharger bearing damage

Black
Blue Smoke
Oil Leak at Compressor

Dirty air fi lter system
Excessive fl ow resistance in exhaust system/ leakage
upstream of turbine
Valve guide, piston rings, engine or cylinder liners worn/
increased blow by
Dirty compressor or charge air cooler
Turbocharger bearing damage

Black
Blue Smoke
Oil Leak at Turbine

Valve guide, piston rings, engine or cylinder liners worn/
increased blow by
Turbocharger bearing damage

Black
Blue Smoke
Noisy Turbocharger

Excessive fl ow resistance in exhaust system/ leakage
upstream of turbine
Dirty compressor or charge air cooler
Turbocharger bearing damage

Black
Blue Smoke
High Oil Consumption
Compressor/Turbine Wheel Failure
Insuffi cient Power

Turbocharger bearing damage

Black
Blue Smoke
High Oil Consumption
Compressor/Turbine Wheel Failure
Insuffi cient Power
Oil Leak at Compressor

Turbocharger bearing damage

Black
Blue Smoke
High Oil Consumption
Compressor/Turbine Wheel Failure
Insuffi cient Power
Oil Leak at Compressor
Oil Leak at Turbine

Turbocharger bearing damage

Black
Blue Smoke
High Oil Consumption
Compressor/Turbine Wheel Failure
Insuffi cient Power
Oil Leak at Compressor
Oil Leak at Turbine
Turbocharger generates noise

Turbocharger bearing damage

01 ENGINE

28

Turbocharger Diagnosis by Symptom

Possible Cause

Symptoms

Black smoke

Blue smoke

High Boost Pressure

Compressor/ turbine

wheel damage

High oil consumption

Low power/low boost

pressure

Oil leak into

compressor

Oil leak into turbine

T

u

rbocharger noisy

Dirty air fi lter

Inlet duct distorted or leaking

Outlet duct distorted or leaking

Overfi lled crankcase

PCV plugged or lines distorted

Turbo oil inlet line plugged or
distorted

Turbo oil inlet line leaking

Turbo oil drain line plugged or
distorted

Turbo oil drain line leaking

Low engine compression: valve
guides, piston rings, cylinders worn/
increased blow by

Excessive fl ow resistance/
backpressure in exhaust system or
leakage upstream of turbine

Fuel system problem

Dirty compressor or charge air cooler

Waste gate control valve does not
close

Turbocharger bearing damage

Foreign body damage to
compressor or turbine

Engine air collector cracked or loose
gaskets

Turbine housing/fl ap damaged

Insuffi cient oil supply to turbocharger

Coke and sludge in turbocharger
center housing

Waste gate control valve defective

Exhaust gas leakage between
turbine outlet and exhaust pipe

01 ENGINE

29

Lubrication Routing Diagram

Coolant Routing Diagram

The coolant lines run from the cylinder head to the EGR valve and turbocharger.