Coupe GT L5-2226cc 2.22L SOHC (KX) (1986)
Air/Fuel Mixture: Testing and Inspection
After-Start Warm Up Enrichment
Fig. 1 Warm up enrichment current graph
Fig. 7 Differential Pressure Regulator Test Harness
After the engine has started, the control unit continues to enrich the mixture with differential pressure regulator current that is higher than normal
warm up enrichment, Fig. 1.. This ensures that the engine will run smoothly for the first few seconds of operation. The level of after start
enrichment is dependant on the engine coolant temperature. Duration of after start enrichment is approximately 40 seconds. To test the after start
enrichment:
1.
Connect differential pressure regulator test harness (VW 1315A/1), Fig. 7, between the harness plug and the differential pressure regulator and
hook up a multi-meter set for 0-200 mA.
2.
Unplug harness connector from coolant temperature sensor and leave open.
3.
Remove fuel pump relay.
4.
Pull high tension coil wire from distributor cap and ground it.
5.
Crank starter for three seconds and return ignition switch to the ON position.
6.
Current should be at least 120 mA for 30 - 60 seconds, then drop to 80 - 110 mA.
7.
If current is not within specifications;
a. Check for open circuit in wire between terminals 24 on control unit plug, and 15a on starter.
b. Check between control unit plug terminals 21 (coolant temp sender) and 2 (ground). Resistance should be:
Approx. 2.5K ohms @ approx. 20°C (68°F)
Above 2.5K ohms @ coolant temp. below 20°C (68°F)