Porsche 944 - Air Flow Sensor Checks; Temperature Sensor (Intake Air) Check

28
Ignition System
TEST POINT 6
Air Flow Sensor
1. Push back protective sleeve of the air flow sen-
sor connector. The connector remains attached.
Connect voltmeter to terminal
9 and to terminal 6
on the rear of the connector.
Specification: more than
8 V.
2. Remove air cleaner.
Connect
voltmeter between term. 7 and ground.
Specification:
approx. 150 to 250 mV.
3. Push sensor plate to full throttle position with a
not·to·hard, smooth item inserted through the
filter intake opening.
Voltage rises above
8 V with sensor plate fully
open (switch over test range).
The sensor plate must
not stick and return to off
position on its own when released.
28.28
Troubleshooting DEE
944
4. Check temperature sensor I (intake air tempera-
ture).
Turn off ignition and pull off plug on air
flow sensor. Connect ohmmeter between term. 6
and 22 on air flow sensor (both outer flat male
plugs).
Specification at
15 to 30° C: 1.45 - 3.3 k-ohms.
Note
Interruption on temperature sensor causes richer
mixture.
Short on temperature sensor causes leaner mixture.
Printed in Germany- XXIV, 1991