Decal System Relay

SYSTEM FAILURE SYMPTOMS:
Stalling on deceleration.

TEST:

1. Connect a 12V test light from +12V to the red wire on the decel solenoid located on the air flow sensor bellows.

2. Connect the pulse ratio meter to the Lambda system diagnostic plug and disconnect the oxygen sensor lead.

3. Simulate a hot engine by placing a jumper wire between the two wires on the thermal contact on the front of the thermostat housing.

4. Accelerate the engine to 1600 RPM and allow the throttle to close rapidly. The test light should come and then off again as the engine speed drops below 1375 RPM as indicated on the car's tachometer. Simultaneously the pulse ratio meter should lock on 60/40 and then revert to 50/50.

5. If inoperative, check at the relay socket.



Terminal 31b Ignition dwell signal
31 Ground
15 +12V with fuel pump relay bypassed
XI Grounding this terminal will lock the Lambda system on a 60/40 ratio when the engine is running
30 Grounded when the throttle is closed
X2 Grounded when the engine temperature is above 120°F and time relay is not in the hot start enrichment mode
87 Jumping the terminal to ground should cause the engine to stall by activating the decel solenoid.