This has just started happening on cold mornings - what's going on?? The radio has worked fine since put in about 18 months ago. Only been monitoring this for a few days but it seems to be OK once the engine is warm. Pi55ing me off!! Car is my00 with Kenwood headunit and front speakers.

This in my experience would usually be apparent as soon as the radio was fitted? You can buy a noise supressor which cuts intefernce for about £20. Have you added anything to the Ice setup lately?

Ohhhhhh, i've just read your post again, i can't understand why the problem goes when the car is warm??????????? Maybe the noise thingys won't be the answer :(

The car was just serviced before I noticed this (30k) - wonder if they have changed something? It is possibly just coincidence that the interference has gone when the enginge is warmed up but this seems to have happened the last couple of days.

[Edited by Boost II - 2/18/2003 1:22:23 PM]

Hi Boost

Problems like this are, more often than not, caused by ground-loop problems (In English, where the earth point of the stereo isn't quite the same as the rest of the car ;)) This then allows any noise on the power supply to be picked up by the stereo and all goes pear-shaped :(. You can then "fix" the problem by putting in suppressors and stuff, but you're treating the symptoms, not the problem.

First suggestion would be to check the earth connection at the battery - make sure it's done up tightly. Also make sure the stereo's connected securely too.

After that, check the ignition leads - again, you're making sure they're connected properly. (I don't suppose they changed the leads/plugs as part of the service did they?)

Final check, make sure the alternator leads are tight.

Once you've done all that, you should be all oily, and the noise should've calmed down ;) If not, shout some more

Thanks for the reply Globbits - I've had a quick look at some of the things you mentioned and yes they did change plugs at the service. Can't really see anything wrong though. The problem is that when I am home and the engine is warm there is no problem to try and fix. Yet again I had the interference this morning on leaving for work, although it only lasted a coouple of miles today - perhaps because it was a little warmer overnight?? Could it just be some resistance changing somewhere as the wires get hot? Not sure whether to mention this to the servicing garage as they might think I am crazy, neither can I be sure that it is something they have done.

The HT leads sound like the most likely culprit to me. They may be cracked/damaged and when warm they'll expand enough to fill the crack.

Disconnect 'em, give 'em a blast with something, then grease them and reconnect.

errm, you may have assumed too great a level of knowledge on my behalf. We are talking about the red leads that connect to the spark plugs,yes? What may be cracked? - the wire or the insulation? How will blasting them with something help. I can just about get my hands to the spark plugs - how do I disconnect at that end - it feels like there is a sort of T shaped piece under the rubber hood - do I just yank on it?
Cheers :)

It could be anything, that's the prob: I've known them fail in the middle...

Yep, it's the things that go into the end of the cylinders from the distributor-thingy (don't know what it's properly called).

First off, just check they're seating properly at both ends...

I too seem to have radio interference since my 30k service a couple of weeks ago - same story, stereo's been in for over a year with no problem. Interference is on the radio only (ie it's not noise on the power supply) and is a revs related "clicking". Haven't got as far as looking at anything yet though - hardly use the car at the moment.

Dave

If it's just on radio, it is most likely HT interference.

My car does this if I drive past an old car with noisy leads.

My RB5 has been doing exactly the same thing since it's 60,000 service a few weeks ago!!! I notice you are from Herts as well - didn't get yours serviced by Quenbys by any chance? Seems odd that it has happened to several cars. I am a bit wary of yanking off plug leads etc but might have a bit of a fiddle and see what happens!

Yes - it was Quenbys, first time I have used them for servicing. I'm going to have a look this weekend when I've got some decent daylight to check the seating of the leads on the plugs. If it doesn't do any good I shall call the dealer back. Only thing is that by the time I have driven up the A1(M) the problem will be non existent and they'll try and claim it is because I have fitted a non standard headunit :rolleyes:

believe it or not, you can buy "audio grade" HT leads... Or at least you could around 4 years ago when they were launched... Not sure if there's a set for scoobs yet.

It sounds like the leads aren't seated properly - just try to push 'em in!

I think it's always worth running a seperate power cable direct from the battery (via a fuse :D) and also an earth direct from the head unit to a clean (unpainted) 'chassis' earth, the same connection then continuing to an earth on the bulkhead (if the 'chassis' earth isn't the bulkhead already). Amazing what it can do to the overall sound quality as well as buzzing noises.
Oh - the earths are best with those nasty looking little washers with the jaggledy bits on them to cut a little into the metal.