Hello All I have a 1999 550 and whenever i make a sharp turn or a fast U turn left my car loses power as i am coming out of the U turn for a few seconds, and then it will suddenly deliver all the power back. Knowing that during that time i never took my foot off the pedal. And even if i remove my foot off the pedal and but it down instantly it will not accelerate. any help would be greatly appreciated
Do you get any warning lights? Battery/Alternator? SLOW DOWN? ASR? Does it feel like you're losing one engine bank? I assume you have plenty of fuel. I suppose it could be anything. Acceleration forces are going to affect lots of things. Do you have an OBD2 scanner? Have you had any maintenance done recently?
I got the slow down message once and the problem was a fuse and i had a problem with the fuel delivery, my car did not start every time. That is fixed now. The problem is it only happens in U turns that are big ones, under bridges for example.
I think you've lost me .... Image Unavailable, Please Login I can't see the significance of making a U Turn under a bridge. Sounds like something lost in translation. Interesting. Can you recall the fuse? The Thermocouple ECUs, for example, which generate the SLOW DOWN lights, don't even have fuses. Without codes or warning lights, it's hard to know where to start looking for faults.
I was not a fuse, wrote that by mistake. It was a sensor that was giving me the slow down light. When i checked the car with an obd scanner nothing came up
@vee12 When we met to give you the fan harness, Didn't you tell me about a similar powerloss problem you were troubleshooting in long sweeping turns? Ever figure out what yours was?
Sound like fuel sloshing away from the outlet from the tank under lateral acceleration, allowing air into the fuel line to me. Was the level in the tank fairly low at the time?
I honestly do not remember how much fuel was in the tank when it happened twice, but i already have a problem with not being able to fill the fuel tank, i have a post about it. Whenever i try to fill the tank the nozzle stops every 5 or 6 seconds into filling. I just ordered the two canisters in hope it will solve the issue.
spirited driving or grandma U-turn? My 1st thought is you getting on it and the ASR triggering. Just to make sure if you don't know what ASR feels like turn it off and hit the U-turn again and see what happens? But don't go so crazy that you loose control because all this time ASR has been saving you...
No the ASR is not getting activated. I keep my foot on the pedal coming out of it and the power goes away, then kicks back on in a few seconds. It throws your head back when the power comes back.
Maybe you still have fuel supply issues. Perhaps there is some debris floating around in the fuel tank and/or the little filter on one of the pumps is not fitted properly.
Yes, went through the entire car. Fuel pumps, ABS ecu, thermo-couplings, O2 sensors/connectors, fuse box, etc....problem still happened. No CELs, just would go into "limp mode" about half way through a big steady right hand turn. Left hand turns had no ill effects. Finally found the fault in one of the Motronic 5.2 ECUs. Currently looking for another one to clone.
