Droning noise from underbonnet, fuel pressure regulator?
 

Hi all, my 04 cdti drones on the overrun, I'm led to believe it's a possible fuel pressure regulator problem?

The UBP has been replaced as it failed and I've also changed the fuel filter, no difference.

Have also read a few threads but they didn't seem to actually conclude what the problem was?

Do I need an earlier type regulator or is there a way to stop the droning noise, maybe with a weight or dampener to absorb the frequencies?

It's a well known issue with some Mk2 diesels and although the fuel pressure regulator is implicated, fitting a Mk1 regulator isn't guaranteed to fix it. Seems worth a shot though, cos it drives you mad, apparently.


TC

It only drones on the over run.---:shrug:

Why should that make a difference. The regulator works all the time.

Got any loose bits under the bonnet ?---:D:D:D

Some reading: https://www.the75andztclub.co.uk/for...ator+resonance


TC

It'll drone on the overrun as that's when the regulator is working hardest isn't it?

Foot flat to the boards and there isn't a squeak from it, once the fuel pressure isn't required it moans away until I feel sorry for it and floor it again. :)

But yeah, after a while the novelty wears off.

Did the pipework change on a mk2 or literally just the regulator?

Would a remap help in that it might change the behaviour of either the pump pressure regulator, or if present, the one on the injector rail?

Thanks TC, will get stuck into that with the bedtime cocoa..... :)

So having read the thread, is it likely this would fit a new style regulator and possibly cure the problem?

Interesting to see all the other manufacturers that use that same pump, wonder if they've had issues other than the BMWs mentioned in the thread.

https://www.ebay.co.uk/itm/333151619688

You mean fit the old type. From what I've read it's not a guaranteed fix, but as I said earlier, maybe worth a shot.


TC

Hi TC, no I meant would the seal kit I linked to fit a new style regulator as I read in the thread you linked that people were putting it down to no rubber O ring fitted or different gauze filter.

Another quick question I had, seeing as the Rover Ron boxes or T4 remap would change the fuel pressure readings that the ECU would see, has anyone ever cured or made the noise worse by fitting a tuning box etc?