BWM 318is heating tap knock....driving me nuts, fix anyone?

[27tim]

I was driving my gf's '98 318is the other day when I pulled up next to a rattly old diesel at some lights, I wondered how the driver could stand the constant knocking every 20secs it was making. Unfortunately, much to my displeasure he pulled off and I could still hear the knocking.

After talking to the garage today they told me it was a known fault and it was 'tap' on the heater opening and shutting. He had no suggestions. Does anyone here know of a fix?

Cheers

Tim

[jamesson]

I had this on my E36 and was told there was no fix as such. The dealer said it was due to some sort of heat regulating valve or something opening and closing, and because of its proximity to the dash, the noise travelled through. I remember thinking what nonsense because I can't imagine BMW putting a car into production with that kind of characteristic.

Let me say here and now I know very little about mechanics, so if someone has a better explanation, or the above is tosh, I won't be offended if you contradict me!

Interestingly, having bought back the very same E36 three years later, the noise has gone. No idea what the interim owner did to it, if anything, but it's worked!

[27tim]

Thanks for the confirmation that I'm not going nuts, thats exactly the description I had yesterday! :-)