Odd noise on acceleration? + backfiring exhaust?

[probedb]

Hi all,

I have a strange problem (?) with my car, a lot of the time when I accelerate I get this weird noise, sort of like a vibration/air sound, quite difficult to describe. At first I thought it was the typical moo sound but my air pump is now attached to the filter (HKS Racing Suction) so don\'t think it can be that? It\'s most noticable at low revs and just tapping the accelerator will produce the noise.

Another problem is that my exhaust sounds like it\'s backfiring and has begun doing it more recently. It\'s usually if I suddenly take my foot off the accelerator.

I\'m not really sure what either are and if any technically minded people are within me driving from Chesterfield i\'d be happy to take someone for a drive to see what they think. Really trying to avoid any costly repairs until the engine is out at the end of Sept.

I\'ve been slighty lax with maintenance but doing an oil change this week all being well. Pip serviced it in Jan and it\'s done about 2k miles, should I replace anything else?

Car has HKS Racing Suction Intakes and Super Drager exhaust but everything else is standard as far as I\'m aware.

Cheers!

Paul.

[gmogle]

When I fitted my Racing Suction kit I found that the metal pipes would catch on the Strut bracewhen I reved the engine so had to adjust hte mushroom filter linking bracket to pull the pipes down.

Also check that the HKS mushroom filters dont catch on the bonnet.

May be worth having someone rev the engine and while you are looking in the enginebay to see if you can pinpoint the source.

[James B]

In my experience, if you are booting it and you suddenly lift off my FD will backfire as when changing gear ....... I guess this is excess fuel.

Firework like backfiring when you are accelerating needs looking at as again, in my experience this is fuel shortage.

Can you try explaining your vibration / air sound more descriptfully.

J

[probedb]

I think it could well be the filters thinking about it, I\'ll have a proper check when I get in this evening and adjust them if necessary.

Thanks for the info on backfiring, was just a bit nervous it might be a bit worse than that

[checkpoint-direct.co.uk]

Unplug your air pump.  I found a plug unplugged under the engine bay so i plugged it in and what a noise!  sounds exactly like your scenario just thinks it reverbs through the metal piping as i had the blitz induction kit on as well so someone had already unplugged it.

[probedb]

I\'ll give that ago. I\'m getting rid of the cat so I guess I don\'t really need it after that. Will unplug just to see if the noise goes away

[James B]

You will find it may go a bit haywire on idle and the A/F readings will go funny.

J