What causes rough idle on a K Jetronic?

What causes rough idle on a K Jetronic?

The movement of the control plunger will be limited if the cold control pressure is too high. This in turn will limit the amount of fuel able to be delivered through the injectors. The result will be a lean ratio and will cause rough idle. 2: Auxillary air valve defective.

How to fix a K-Jetronic cold start injector?

Remove the air cleaner and loosen the center line on fuel distributor. This will relieve the control pressure. Press down on the center of the plate and you should feel no resistance or binding. 3: Defective cold start injector.

How to troubleshoot a K-Jetronic time switch?

Press down on the center of the plate and you should feel no resistance or binding. 3: Defective cold start injector. If the injector does not function, the air-fuel ratio will be lean, preventing easy start up…tho, it may still start. 4: Shorted or defective thermo time switch.

Where is the pressure regulator on the K-Jetronic?

The lower connection hose is attached to the pipe that is connected to the K-Jetronic fuel distributor control input. There is also a 12V power socket on the top of the CPR. It is connected to a bimetal plate heater that is located inside and used to regulate the fuel pressure.

Is the K-Jetronic trouble, rich mixture when cold?

When cold the mixture is very rich and the car idles rough and black smoke is produced. The auxiliary air valve seems okay. The cold start injector does not leak and is closed. The injectors spray fairly even and the amount is very close to equal on all 4. The resistance in the spark plug cables is 1 kOhm as it is supposed to be.

The movement of the control plunger will be limited if the cold control pressure is too high. This in turn will limit the amount of fuel able to be delivered through the injectors. The result will be a lean ratio and will cause rough idle. 2: Auxillary air valve defective.

Remove the air cleaner and loosen the center line on fuel distributor. This will relieve the control pressure. Press down on the center of the plate and you should feel no resistance or binding. 3: Defective cold start injector.

Where is The Wur on a K-Jetronic?

Connect your gauge in the inlet line, with tap on the WUR side of the gauge. Start engine, preferably from cold. Note the initial gauge reading, and then wait until it stabilizes at the warm setting.

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