Results References

17th December 2003

Taken from 4AG-E 20Valve Engine Repair Manual page FI-30


HINT: Engine ECU data can be monitored by hand-held tester.

  1. Hook up the hand-held tester to the check connector.
  2. Monitor engine ECU data by following the prompts on the tester screen.

Please refer to the hand-held tester operator's manual for further details.

(Engine at normal operating temp.)

Item Inspection condition Reference value
INJECTOR Engine cold to hot Gradually decreases
Engine idling at normal operating temp. *1 Approx. 3-4 msecs
IGNITION Increase engine speed Gradually increases
ISC DUTY Engine idling at normal operating temp. *1 Approx. 29-39%
A/C Switch ON Duty ratio increase
A/T shifting in "D" position Duty ratio increase
ENGINE PSD RPM kept stable (Comparison with tachometer) No great changes
INTAKE MAN Engine idling at normal operating temp. *1 Approx. 160-350 mmHg
Increase engine speed Gradually increases
COOLANT TEMP Engine at normal operating temp. 75-95 Celsius (167-203 Fahrenheit)    *2
THROTTLE Closed throttle position Below 5 degrees
Wide open throttle Above 70 degrees
From closed throttle position to wide open throttle Gradually increases
VEHICLE SPD During driving (Comparison with speedometer) No large differences
TARGET A/F L Engine idling at normal operating temp. 2.5 +/- 0.7V                                            *3
A/F FB LEFT RPM stable at 2,500 rpm with normal operating temp. ON
KNOCK FB Depress throttle pedal suddenly during idling ON
STA SIGNAL During cranking ON
IDL SIGNAL Closed throttle position ON
Ox L RPM stable at 2,500 rpm with normal operating temp. RICH LEAN is repeated

*1: All accessories and A/C are switch OFF.

*2 If the engine coolant temp. sensor circuit is open or shorted, the engine ECU assumes an engine coolant temp. value of 80 Celsius ( 176 Fahrenheit).

*3 When feedback control is forbidden, 0 V is displayed.


The application conversion for use with 20v AFM aka "Silvertop" are "guessed" as follows: -

INTAKE MAN = Intake Manifold Vacuum to be replace by Air Flow Meter's Flap voltage. Operation of AFM is 5V to (zero) 0V. Therefore at idling is assumed between 4V to 3V and reduces as engine increase rpm.

Other issues

It is only known now that the TPS can have such a high tolerance. Below 5 degrees when throttle is fully closed.

TARGET A/F L = mine is 0V, oh shxt :( no closed-loop fuel delivery optimisation / compensation :( mah ha ha ha ha ha

The O2 sensor needs to be changed :( meh eheh heh eh hheh ehe mind as well take it out and throw away. Now where to find a camry and sneak under it to steal a O2 sensor :) hehehehehe hahahahah muah ha ha hahah ha ha. Don't tell anyone :) hehehehehehe

Ox L = mine is unknown :( meh eheh heh eh hheh ehe 


  1. Diagnosis System
  2. Diagnostic by DCN Pro
  3. Diagnostic for a friend
  4. Different Diagnosis
  5. Results 1
  6. Results 2
  7. Results 3
  8. Results 4
  9. References



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