Car felt slow today...

Alin10123 · 23rd July 2010, 08:56

Hey guys,
M5 has been running awesome ever since i installed the RPI scoops and BMC filters. The car felt alive and very peppy. Put a smile on my face when i mashed down the gas pedal even in S400 mode. The weather has been pretty hot lately, but the car still felt very alive.
Today i ran into a situation where i had to sit in a little bit of traffic. I normally dont let the car sit there and idle for too long but it was very hot outside. The engine ended up idling for about 5 minutes and then i shut the engine off when i determined i wasn't going to get anywhere fast. After about 10 minutes of sitting in the bumper to bumper traffic, i started up the engine again. But we never got faster than a crawl for a little while. Then there was stop and go for a little while.
Later on i turned onto a road where there wasn't much traffic. I did my usual thing and hit the gas pedal. For some reason the car did not feel as fast as it did earlier in the afternoon. I thought it was because the outdoor temp gauge was reading 100 degrees F and perhaps the engine was a little heat soaked. So i waited until it got dark outside and the temperature outside went back down to 85 degrees. I got on the gas again, car still didn't seem as it was earlier in the day before the heavy stop and go traffic.

Anybody ever have this experience before? What can be done to get the engine back to normal? Is this going to go away after a while? Car seemed pretty slow tonight driving home.

Dave321 · 23rd July 2010, 13:54

Mine does this sometimes, throttle feels lethargic ! Dealer plugged in but says no faults which is a bit annoying at times, maybe it's engines way of protecting itself when it gets hot?

Alin10123 · 24th July 2010, 18:10

Hmm... seemed to be a little better yesterday even though it was still 85-93 degrees outside.

Ahmed · 25th July 2010, 07:44

It's summer, don't worry too much about it!

///power · 25th July 2010, 08:45

Clean them MAFs, you'll notice the difference.

Alin10123 · 25th July 2010, 19:50

The MAF's needing cleaning in the e39 was fairly common. Is that supposed to be an issue in the e60 as well? I dont hear about it too often. By the way, i only have 26000 miles. Seems very low mileage for needing to clean them...

///power · 25th July 2010, 21:31

Can't think of anything else.. Is the engine running smooth? If yes, it might be the hot weather as Ahmed said.

Alin10123 · 26th July 2010, 11:18

I guess it's possible that the MAF's need cleaning. However, if that were to happen wouldn't it happen gradually? This was sort of me feeling the major difference after a bunch of stop and go traffic on a hot day. I'm going to drive her a few more days and see what happens. She was driving better today. It was about 89 degrees outside. I think the stop and go probably got the engine very heat soaked.