a couple of questions - The Unofficial BMW M5 Messageboard (m5board.com)

pfinucane · 25th May 2006, 17:54

Hi all,

I have a couple of questions re my 3.6 m5.

It has been idling a little lumpy so I changed the throttle switch & plugs etc & sometimes when the steering is on full lock it stalls which I find very odd-it has a very slight exhaust blow from where the cats are joined to the downpipe (I think) & also it smells of petrol when revving hard sometimes-also there are carbon deposits on the plugs & tail pipes-dist cap & rotor arm have both been replaced.

On my old 525 sport I had a hks induction kit which worked well with the bbtb I had fitted - I was considering fitting one or maybe a K&N to the m5 & wondered what peoples opinions are.

Paul

illjah · 25th May 2006, 17:57

Quote:

Originally Posted by pfinucane

I was considering fitting one or maybe a K&N to the m5 & wondered what peoples opinions are.

Not favourable i can you now!!!

Do a search, the air filter is pretty much impossible to improve on the m5. many people who have had k&n's on say they noticeable DECREASED power.

illjah · 25th May 2006, 18:00

Quote:

Originally Posted by pfinucane

it has a very slight exhaust blow from where the cats are joined to the downpipe (I think) & also it smells of petrol when revving hard sometimes-also there are carbon deposits on the plugs & tail pipes-dist cap & rotor arm have both been replaced.

carbon on tail pipes is pretty normal.

on plugs, obv running a bit rich. Check your fuel pump is delivering correct pressure, smell of petrol is a little worrying, obv check ya fuel lines. My 3.6 just recently has started smelling of petrol a bit too, and i too think I have some minor blow but from more up near the manifold.

farrell · 25th May 2006, 18:42

Yes
K&N filters.
I would wait for the promotional offer they do where they give you a Free Maf with every filter...

The oil that is within the filter sponge gets into the intake & coats the MAF hot wire sensor.
The oil carburises onto the sensor & limits its operation until you have such a poor running car that it wont idle or part throttle pickup will be juddery.

It could get worse than that.

Dont consider it.
Farrell

Sebring NL · 25th May 2006, 18:52

I had one in my car when I got it. I only discovered it before the Ring trip, and boy I was surprised by how bad it looked. I never experienced any trouble with the car whilst the filter was in, but after getting an OEM filter to replace it, the second I fired her up it felt less restraint. I was happy to have it done before the Ring

pfinucane · 25th May 2006, 18:58

I know that I have a k&n panel filter fitted in the standard airbox-looks like I should replace that now then with a standard one.

Paul

Quote:

Originally Posted by Sebring NL

I had one in my car when I got it. I only discovered it before the Ring trip, and boy I was surprised by how bad it looked. I never experienced any trouble with the car whilst the filter was in, but after getting an OEM filter to replace it, the second I fired her up it felt less restraint. I was happy to have it done before the Ring

Sebring NL · 25th May 2006, 22:17

yes

illjah · 26th May 2006, 14:18

The BMW paper one performs superbly if changed at the right intervals. There is no need to go non-OEM.