Yet more Cruise Control

Hi Guys,

I know this subject has come up loads of times, but I'm still no nearer a solution to my problem and with a long trip coming up it'd be good to fix it.

To start with, this is on a '98 4.6 HSE. Basically the light comes on on the switch, but it doesn't appear to do anything. I'm assuming the buttons on the steering wheel are ok as the radio ones all work.

I've changed the two little rubber hoses going to the T piece, but where exactly does the long third one go? It seems to disappear into the bulkhead somewhere. I had the panel under the steering wheel off the other day to do something else and I half expected to see it in there somewhere but I didn't spot it.

Are there any tests that I can do on the cruise control while stationary to try and work out what the problem is? Should there be a vacuum in the long pipe when the engine is running for example?

It's just one of a long list of things that needs fixing, but it'd be good to have some ideas to try!

Guy

have you tested the little vaccum thingy near the eas pump box? check connections.

gavbriggs said:

have you tested the little vaccum thingy near the eas pump box? check connections.

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Hi Gav,

How does one test it? I've tested that it exists!

That's kind of why I was asking whether the pipes should have a vacuum in them when the engine is running as I have no idea what it should be doing!

Guy

it should compress the bellows but you need to be doing more than 30 mph!!!

i'm not sure if its just a switch tho.

i assume you have had the wires out of it and made sure they are connected and clean, this ive seen this issue before.

gavbriggs said:

it should compress the bellows but you need to be doing more than 30 mph!!!

i'm not sure if its just a switch tho.

i assume you have had the wires out of it and made sure they are connected and clean, this ive seen this issue before.

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I thought it might, but it's a bit tricky to see when I'm driving along! I assume it's doing nothing since the cruise control is doing nothing - I've made sure the cable connecting to the throttle cable is properly adjusted so I assume any movement on the bellows wouild be noticeable.

So the vacuum to compress the bellows only exists at the correct speed so it can't be tested when stationary?

Brings me back to my question of where on earth is the other end of the long pipe? It's possible the hidden end is knackered like the rest of them were. Actually they weren't knackered, thinking about it - someone had replaced them with windscreen washer pipe (yes, the really floppy collapsible kind) so I had high hopes that replacing them would fix it but it didn't.

I've not pulled the wires out of the bellows unit. Actually, I don't recall actually seeing any - I'll have a look on my next ciggie break.

Guy

Aha! Is that box thing under the bellows the vacuum pump?

Couldn't see very much just now as it's dead gloomy here and I don't have a torch, but I'll have another poke around when I get home, but I did see some very oily wires coming out of the bottom of it.

Hello Kooky-guy

I have had a load of problems with my cruise, hopefully i've got to the bottom of it now though. i'll tell you what i did. I changed the pipes by the t-piece, as they were all perished. I took the pipe off that goes into the centre of the back of the diaphragm, pulled the diaphragm together and put my finger over the little black tube sticking out and if there are no leaks it should hold together. Incidentally, the long pipe that goes across the back and into the bulkhead, that ends up on the back of a cruise control vent/switch, on the back of the brake pedal. I blew down mine (or tried to!) and there wasn't any leaks. to get to the cruise control vent/switch, you will have to remove the fascia panel under the steering wheel and i also removed the black kick panel. I also had to pull down the plastic blower ducting, to get better access. You can then pull the switch out with the vacuum pipe on it. I checked the switch for continuity, which was ok, but i replaced it in the end as it was only about £9 from Land Rover. I trimmed the end of the vacuum pipe and re-fitted it (also with a dab of superglue, just to hold it on a bit better, as i found that sometimes the pressure blew it off the back of the switch, but do this at your own risk!) back on the switch. i then took the vacuum pump off and checked it with a direct feed, that was ok. the next step was electrical, so i looked at rave under ETM and B5 Cruise Control (page 65 i think). all you need is a multimeter and even i managed to follow the instructions!! All it does is gradually elimate everything one by one, by using the multi-plugs from the Cruise Control ECU and relay (which is all i needed to check, as the fault with mine is either with the steering wheel switches or the spiral cassette). I think it goes a bit more in depth later if you can't identify the problem.

Kev

Excellent Kev!

Cheers, I'll try all that. Great idea for testing the bellows - never occurred to me to try that!

I'll keep you posted (although I'm supposed to be trying to fix my leaking EAS connectors this evening).

Guy

No problem, glad i could be of help!

Kev

Hi Guy the long hose is attached to the brake peddle via a gismooojamaflip thing. This can perish and cause air leaks, is the motor ok? Mine works intermittantly I've traced this to the motor.

Good luck Jon

jonny427 said:

Hi Guy the long hose is attached to the brake peddle via a gismooojamaflip thing. This can perish and cause air leaks, is the motor ok? Mine works intermittantly I've traced this to the motor.

Good luck Jon

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Motor? What motor?

the motor in the bit you found near the eas, its a vac pump i think

gavbriggs said:

the motor in the bit you found near the eas, its a vac pump i think

Click to expand...

Aaaah. Make sense now. Does it run all the time, or only when the cruise control ecu decides it should?

It seems ridiculously complicated, all this. My old Vectra was from the same era and the cruise control on that was all electronic - none of this Victorian vacuum nonsense! I wonder if that's why my heated seats don't work - the boiler needs more coal or something?

Still not managed to look at it properly yet. Might have to wait until the weekend now as it's dark by the time I get home these days. Did I miss Summer?

Guy

the veccy and omega system are the same, i have one of the units and its just a little motor that holds and adjusts the throttle. i agree alot simpler to fit and install.

no plumbing to feck around with!!!

I replaced the pipes at the bonnet end £2.50 replaced the dash board switch £2.99 ebay ( just in case ) saw a 2nd hand vacuum pump thingy on ebay £11 took 5 mins to fit took it for a spin not even expecting it to work but hey presto it did!