Download Ford EEC IV - T.I. Performance

Ford EEC IV
Operation and Testing
Overview
ECT
MAP/BARO
TPS
CKP/CMP
O2S
EGR Position
ACT
KS
BOO
AC
Power Steering
PCM
A/F Mixture
Ignition Timing
Idle Speed
Thermactor Airflow
Canister Purge
EGR Flow
TCC
AC Fan
WOT Cut Off
Inlet Air Temp
Fuel Pump Relay
Turbo Boost
Operating Modes
Base Engine Strategy
MPG Lean Cruise
Modulator Strategy
Limited Operational Strategy
Adaptive Strategy
Base Engine Strategy
Used to control warm engine running
Open Loop starts at 130o
 Warm up mode sub modes

Cranking
 Closed-throttle
 Part throttle (closed loop)
 Wide-open throttle (WOT)


PCM controls actuators for good
driveability
MPG Lean Cruise
Some engines beginning 1988
Certain criteria are met
Goes out of closed-loop fuel control
Very lean for economy at cruise
Modulator Strategy
Conditions that require significant
change from Base Engine Strategy
Cold engine
 Overheated engine
 High altitude

Limited Operational Strategy
Component Failure
Protect other components

Converter
Substitute values from another sensor
MAP
 ECT
 EGR

TPS
IAT
Disable EGR
Adaptive Strategy
Started in 1985
PCM has base map
Monitors operation and modifies base
map
Compensates for wear etc.

Dirty Injectors
Are in response to O2S
Stored in KAM
Adaptive Strategy
Adaptive Strategy
Adaptive Strategy
Adaptive Strategy
Inputs
ECT
MAP/BARO
TPS
CKP/CMP
O2S
EGR Position
ACT
KS
BOO
AC
Power Steering
PCM
A/F Mixture
Ignition Timing
Idle Speed
Thermactor Airflow
Canister Purge
EGR Flow
TCC
AC Fan
WOT Cut Off
Inlet Air Temp
Fuel Pump Relay
Turbo Boost
Engine Coolant Temp
Thermistor
Voltage to PCM is 4.5 cold to .3 hot
Resistance 470K cold to 1k hot
Influences PCM’s calibrations for






A/F Raito
Idle Speed
Thermactor Air
Canister Purge
Choke Voltage, Temp compensated accel pump
Upshift light
Pressure Sensors
MAP, BARO
Pressure-sensitive capacitor
Convert to frequency out
100 Hz no load Idle
 159 Hz atmospheric (WOT)

Voltage will go from 0 to 5 at the
frequency above
Pressure Sensors
MAP used for BARO

PCM uses Key On before cranking and
WOT for BARO calculations.
BARO used with Vane Airflow Sensors
Looks like MAP with collar
Throttle Position Sensor
Some adjustable, some not
Potentiometer
3 wires, 5v reference, ground, signal
Two common problems
Bad spot, signal dropout
 Bad ground

Full reference on signal
 Biased high

Profile Ignition Pickup (PIP)
Hall Effect Switch
Engine speed and crank position
In distributor
One vane narrower for location
Profile Ignition Pickup (PIP)
On DIS sensor is on front of engine
One vane for each pair of companion
cylinders
Most PIP signals go from .4v or less to
battery voltage at 10o BTDC
Cylinder Identification (CID)
Used with Distributorless Ignition
PIP doesn't know which stroke
Driven at
cam speed
Also used
for SFI
4 Cylinder PIP CID
On DIS, 1 & 4 fire together
CID is on crank with PIP
Ignition Diagnostic Monitor
Used on TFI systems
Checks to see that spark occurred
Wire with 22k from Tach wire to PCM
Makes sure SPOUT command is
carried out
Makes sure timing advance is working
Knock Sensor (KS)
Piezoelectric type
Vibration sends signal to PCM
PCM retards timing 1/2o per engine
revolution
Intake Air Temp Sensor (IAT)
Was called Air Charge Temp (ACT)
before OBDII
Thermistor
Voltages and resistance same as ECT
A/F and advance
Used on most Fords
EGR Position (EVP)
Feedback (PFE)
EVP Linear Potentiometer

only monitors position
EVP Black and White
physically interchangeable
PFE is like MAP but gives a voltage

Measures exhaust pressure under EGR valve
PFE measures flow used to



Fine tune EGR position
Fine tune A/F ratio
Modify ignition timing
Vane Air Flow (VAF)
Used with VAT and BP to calculate
Speed Density
Mass Airflow MAF
Beginning in 1988
Uses sample tube
Uses hot wire
Encased in Glass
200o above ambient
A/F and Timing
Transmission Switches
PCM knows if in gear, park or neutral
Affects Idle air control strategy

For A/T because converter loads engine
Response to rapid throttle closing
Transmission Switches
AXOD uses 3 switches
Neutral Pressure NPS
 Trans Hydraulic THS 3-2 Can tell which gear
 Trans Hydraulic THS 4-3 except if it is in 1 or 2

AXOD Trans Temp TTS opens over
275oF

Will apply TCC if temps get high like uphill
climb
Transmission Switches
Transmission Switches
Manual Trans
Neutral Gear Switch NGS
 Clutch Engaged Switch CES
 Wired in parallel so both must be open for
PCM to know car is in gear.

Brake On/Off BOO
In stop lamp switch
A4LD has PCM controlled converter
lockup
Used on most models today
Increases idle when in gear and brakes
are on
May disengage AC on prolonged idle
Vehicle Speed Sensor (VSS)
Speedometer output

Mechanical or electric
speedometer.
8 cycles per revolution
128000 signals per mile
Used for



TCC lockup
Coolant fan control
Identify deceleration
Other Inputs
Power Steering Pressure Switch PSPS
Opens between 400 and 600 PSI
 Increases idle speed

AC Demand (ACD)
AC Clutch Cycling Switch (ACCS)

PCM watches to increase idle speed
Outputs
ECT
MAP/BARO
TPS
CKP/CMP
O2S
EGR Position
ACT
KS
BOO
AC
Power Steering
PCM
A/F Mixture
Ignition Timing
Idle Speed
Thermactor Airflow
Canister Purge
EGR Flow
TCC
AC Fan
WOT Cut Off
Inlet Air Temp
Fuel Pump Relay
Turbo Boost
Air / Fuel Mixture Control
Three types
Feedback Carburetors
 Central Fuel Injection (TBI)
 Electronic Fuel Injection (PFI)

Non Sequential
 Group
 Sequential

Feedback Carburetors
Motorcraft & Carter uses solenoid to bleed
air into idle and main metering circuits
Holley Carburetors
Holley uses
remote solenoid
with similar idle
control
Holley Carburetors
Uses vacuum
diaphragm and
valve for main
metering control
Central Fuel Injection
Low Pressure System

Single injector
Low Pressure System
Two injectors
 Alternates injectors

ECM grounds to turn on
Pulse Width Modulated
Central Fuel Injection
CFI Fuel Delivery
Port Fuel Injection (EFI)
Port Fuel Injection
Non-sequential (EFI)
Group or bank-to-bank

Two Groups
Sequential (SEFI)
Injectors pulsed one at a time in firing order
 Used throughout product line by early
1990s

Injector Removal
Fuel Supply System
Fuel Supply System
Fuel Pump
In tank
 Trucks may have a lift and pressure pump
 Most are around 39 psi
 Pressure relief at 100 psi

Fuel Supply System
Pressure regulator
Manifold pressure modified
 Low of 30 around psi (deceleration)
 High of 39 psi (WOT)
 Turbocharged may go as high as 50 psi
 CFI does not use manifold pressure.

High pressure 38-40 psi
 Low pressure 14.5 psi

Fuel Supply System
Fuel Pump Relay PCM Controlled
Turns on with key for 1-2 seconds or until PIP
signal is present.
Inertia Switch is in series with pump
Thick Film Integrated (TFI-IV)
Thick film refers to the type of semiconductor
Controls spark primary
Sends PIP to PCM
PCM modifies and sends back SPOUT
SPOUT tells TFI when to turn primary
on and off.
In distributor or “Closed Bowl”
Thick Film Integrated (TFI-IV)
Thick Film Integrated (TFI-IV)
TFI Module
Closed Bowl
Octane rod can change base timing while keeping rotor right.
Distributorless Ignition
PCM controls dwell and timing
DIS module is like TFI module
Also uses SPOUT

Now called Spark Angle Word (SAW)
1991 second generation using
Reluctance instead of Hall sensors
35 teeth on crank 36 minus1 for position
Distributorless Ignition
Base Timing Check
Remove SPOUT/SAW jumper
 10o
 Self check adds 20o

Octane adjustment jumper looks like
SPOUT

Retards 3o to 4o and can be left out
Spout Connectors
Idle Speed
Carbs & CFI use
Throttle kicker
 DC motor idle speed control (ISC)


Idle Tracking Switch


Senses closed throttle
PCM then operates ISC
Act as Idle Dashpot
EFI Idle Speed Control
Air bypass solenoid
PCM
Controlled
Duty
Cycle pintle
valve
Also
a dashpot
Thermactor Air Management
Thermactor
Air Bypass
(TAB)
Thermactor
Air Diverter
(TAD)
PCM
Controlled
Thermactor Air Management
CTS Below 50o TAB grounded

Sends air to atmosphere
Between 50 and 190 Bypass valve
sends air to diverter and to manifold
Over 190 closed loop and air goes to
Cat
Bypass at idle, WOT, and with failing
O2S
Open Loop Tip
The fastest way to see if vehicle is in
open loop is to see where the air is
going
Cat = Closed Loop
Atmosphere or manifold = Closed Loop
Provided thermactor system is working
Canister Purge
Three types
Constant purge with no PCM control
PCM controlled in-line solenoid
PCM controlled with temperature
controlled vacuum valve
Canister Purge/Heat Control
To valve that
warms intake
manifold
EGR Control
EGR Control and
EGR Vent
2 solenoids that are
“dithered”
EGR Control
EGR Shutoff Solenoid


Uses one solenoid
Controls ported vacuum
EGR Shutoff Solenoid with Backpressure
Transducer



One solenoid
Strength of vacuum controlled by transducer
Does not have EVP sensor
EGR Control
Vacuum Regulator
Introduced in 1985
and is used for
most applications
EEC IV Diagnosis
Codes follow self test
Codes can be read

Manually
Watch MIL
 Hook up meter

Star II
 Other scan tool

Notice the safety glasses 
Slow and Fast Codes
Slow codes can be read with pulsing
meter or MIL
Fast codes can be read by scan tool
Fast codes precede slow and look like a
momentary flashing.
Diagnostic Connector
KOEO Self Test Procedures
Engine warm
Turn off for 10 seconds
KOEO, then ground STI
Test will run, then read codes
All accessories off
2.5L and 4.9L hold clutch fully in.
KOEO Self Test Codes
KOER Self Test Procedures
Engine warm 2000 RPM 2 min
Turn off for 10 seconds
KOER, then ground STI
Test will run, then read ID codes
Push brake and turn steering wheel
After code 10 (or 1 flash) snap WOT
KOER Self Test Codes
Computed Timing
Pull SPOUT/SAW

Check for 10o with timing light
Reinstall SPOUT/SAW
Run KOER self test

At end of last code, 20o will be added to
base timing for 2 min.
Other Tests
Continuous monitor (wiggle)
After last code, deactivate and reactivate
self test
 Wiggle wires etc. Fault will display

SEFI Cylinder Balance
KOER after last code, tip throttle and
release.