Cruise control fixed!

[PeterH]

I've been at it again today, trying to diagnose a fault with my cruise control, where it would not hold speed, or lately work at all.
I could not hear the little click any more when I pushed the set button and had no cruise control.
The first thing I found was the cable was out of adjustment, which is an easy fix, (see pics).
Next I got under the foot well and found the vacuum switch that rests against the brake pedal was loose in the bracket, thanks to a tiny broken clip, the movement was enough to stop the switch properly engaging.
I followed this guys idea and it worked a treat, a small screw in the end of the plunger effectively gave me enough adjustment to get it working again, I could once again hear the click when the set button was pushed.
Cruise Control Patch/Fix, Brake Switch
Next I checked the hoses were holding vacuum ok, which they seemed to be.
So I tested the electrics of the pump following this thread: P38 1998 Cruise Control Fix (May help someone)
I found the pump to be working correctly, but it would not hold vacuum.
Finally I traced the vacuum leak to the bottom short hose on the actuator (arrowed in the pic). I had replaced the two short hoses recently, but the bottom one was not sealing properly.
I had a smaller gauge hose laying around in the shed, so I cut that to length, put it on, went for a drive, and hey presto, cruise control working once again, and it didn't cost a cent to fix.
Hope that helps someone trying to diagnose a cruise control fault.
Cheers, Pete.

[redandy3575]

I've been at it again today, trying to diagnose a fault with my cruise control, where it would not hold speed, or lately work at all.
I could not hear the little click any more when I pushed the set button and had no cruise control.
The first thing I found was the cable was out of adjustment, which is an easy fix, (see pics).
Next I got under the foot well and found the vacuum switch that rests against the brake pedal was loose in the bracket, thanks to a tiny broken clip, the movement was enough to stop the switch properly engaging.
I followed this guys idea and it worked a treat, a small screw in the end of the plunger effectively gave me enough adjutment to get it working again.
Cruise Control Patch/Fix, Brake Switch
Next I checked the hoses were holding vacuum ok, which they seemed to be.
So I tested the electrics of the pump following this thread: P38 1998 Cruise Control Fix (May help someone)
I found the pump to be working correctly, but it would not hold vacuum.
Finally I traced the vacuum leak to the bottom short hose on the actuator (arrowed in the pic). I had replaced the two short hoses recently, but the bottom one was not sealing properly.
I had a smaller guage hose laying around in the shed, so I cut that to length, put it on, went for a drive, and hey presto, cruise control working once again, and it didn't cost a cent to fix.
Hope that helps someone trying to diagnose a cruise control fault.
Cheers, Pete.

Thanx for sharing this. It may help me.

[Scouse]

The vacuum switch on the brake pedal isn't needed. Mine had a leak in the line/switch somewhere so I bypassed it altogether & the cruise control still works fine. The electric brake switch still kills it when needed.


There's a step by step diagnostic procedure in the ETM that is easy to use.

[poleonpom]

Pete, you're really going to town on that beast of yours. Jonathan

[PeterH]

LOL poleonpom, yes I have been giving it a red hot go of late!
I'm going to be very busy with work again soon, so I wanted to make the most of the time I had to get as many of those things sorted while I could.
It's great to drive now, I love it!
I think I've just about crossed everything off the list...a couple of blown bulbs on the dash buttons to fix...might give the brakes a proper bleed...now what else can I find?