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540 touring
06-24-2007, 06:26 AM
I seem to have lost power, especially when accelerating. My 540 touring auto will do 80mph if I let it accelerate gradually, but kick down produces very little. My cats are rattling and could be damaged. Would this result in the loss of power/performance ? (I'm not using any oil / water, but mpg is down to about 10 !!)

thanks

Dave M
06-24-2007, 06:43 AM
If cats plugged, then yes, performance will suffer.

Other ideas:

O2 sensor(s)?

Does it sound like its missing? Running on less than eight cylinders? Plugs/coils/water or oil in spark plug wells?

Have you pulled your codes (if possible)?

Dave

markus
06-24-2007, 08:54 AM
yea i changed 4 of my spark plugs last week and they were saturated with oil. i still have to do the other side soon. but just doing 4 plugs seem to make the car more responsive and start up faster.

540 touring
06-24-2007, 04:16 PM
If cats plugged, then yes, performance will suffer.

Other ideas:

O2 sensor(s)?

Does it sound like its missing? Running on less than eight cylinders? Plugs/coils/water or oil in spark plug wells?

Have you pulled your codes (if possible)?

Dave
Thanks Dave.
I hadn't noticed it missing or not running on all cylinders. The exhaust (i think cats really) are very noisy when cold, but I'll get the plugs checked. I've just bought a complete magnaflow system but am struggling to get someone to fit it.

How do i pull my codes ?

thanks very much

phil

632 Regal
06-24-2007, 04:56 PM
USA cars stomp test works http://www.google.com/search?q=stomp+test&btnG=Google+Search&domains=www.bimmer.info&sitesearch=www.bimmer.info

bookmark this search link, the one on here sucks.
http://www.bimmernut.com/wwwboard/e34/si.html

How do i pull my codes ?

Ross
06-24-2007, 07:31 PM
A simple way to check for restricted exhaust is with a vac gauge. Hold the engine at a steady speed, three grand or so and watch the gauge. If the vacuum drops off with revs steady then it's restricted.
An overheated cat can fuse into a solid mass really plugging things up.