cruise control problem

Maybe not being able to type or use the spell checker?

I got a gulf GL 1994 and the cruise works foa abt 2 or 3 min then it stop, what can be the cause? Thanks

sorry for the bad quality of my english(for the first comment) and I got an automatic transmisson, does the computer control the speed or is it a vacuum control?

Yes

Yes

Or to be more specific, there is an electronic control module for the cruise control mounted somewhere in the cabin (on A2's it is usually mounted inside the center console, not sure about your A3) that controls a vacuum pump / vacuum solenoid mounted under the hood (on A2 it is close to the firewall under the brake booster). From this pump/solenoid there are vacuum hoses going the the actuator (black bellow that pulls open the throttle) and to the switch at the bake pedal.

The switch at the brake pedal (separate from the brake light switch) does two things when you step on the brakes: It throws open a switch, telling the control module to turn off the cruise, and it opens a valve to let air into the system so that the actuator releases the throttle. In addition, the control module is connected to the brake light switch as well for redundancy (so for the cruise control to fail in the engaged mode, the vacuum valve must fail *and* the brake pedal switch must fail closed *and* the brake light switch must fail open).

I would be suspicious of the brake pedal switch. If you look under the dash around the brake pedal, fairly high up you will find the switch in question. It has two wires and one rubber hose (about 10 mm outer diameter, probably black) going to it. Pull off the hose and unplug the wire connector. Turn the whole switch one full turn closer to the pedal arm and plug back in the wire connector and hose. See if the cruise control stays on now.

I mentioned the connection to the brake lights switch. Some WVs have had this connection, others not. If the brake light switch is adjusted too close to the pedal, this could throw off the cruise as well. This is easy to check. Have a helper stand behind the car and observe the brake lights (or back up against a wall or something so you can see them yourself). Now put your foot on the brake pedal ever so lightly. does the brake lights come on? If the switch is adjusted so close that normal shaking and vibration of a moving car will flash the brake lights, the cruise control will shut off. Not sure how to adjust the brake lights switch on your A3, on the A2s you brutally pull out or push in the plunger of the switch and it will click into position. If your brake lights come on too easily, try extending the plunger one click (it that is how it works on your car).

Finally, and this is only speculation on my part, the cruise control unit *might* have a fail-safe mode where if it needs to turn on the vacuum pump continuously for too long it will shut down the system. If this is the case, and you have anything more than a very small vacuum leak, it could shut down the system. To test for leaks, remove the hose from the vacuum pump (make note of where it goes, the pump has two ports, I believe one white and one black). Then compress the actuator bellow and plug the hose with your finger. Let go of the bellow and see how fast it expands back to rest position. If it takes less than a few seconds to get back to rest position, you may have too much leakage in the system. If I get a chance, I'll do this test on my brother's GTi (with working cruise) and let you know how long it takes for the bellow to extend.

Thanks for your help ! I will get back to you thanks again andre

Hello, I have had the same problem with my 94 Golf TD and the dealer replaced the Cruise Control Servo/Regulator. Fixed the problem for about 6 years and now it is doing it again. The part was covered under the warranty then so I don't know how much one would be.

Hope this helps. Jer.

Hello, I have had the same problem with my 94 Golf TD and the dealer replaced the Cruise Control Servo/Regulator. Fixed the problem for about 6 years and now it is doing it again. The part was covered under the warranty then so I don't know how much one would be.

Hope this helps. Jer.