Hi
My car runs a little 'funny' until it is warmed up...Jerky, sensitivity to the throttle, lack of power. When warm it is much improved but not perfect. I also get an implausible temp reading fault from the computer. I'm thinking of changing the coolant sensor used by the ECU to see if it improves things. The sensor that in the middle of the water pump appears to control the temperature gauge in the dash and that works fine...starts low and moves to the middle when warm. Does this mean the second sensor attached to the water pipe going to the radiator is the one used by the computer??
Any help much appreciated.
Hi
My car runs a little 'funny' until it is warmed up...Jerky, sensitivity to the throttle, lack of power. When warm it is much improved but not perfect. I also get an implausible temp reading fault from the computer. I'm thinking of changing the coolant sensor used by the ECU to see if it improves things. The sensor that in the middle of the water pump appears to control the temperature gauge in the dash and that works fine...starts low and moves to the middle when warm. Does this mean the second sensor attached to the water pipe going to the radiator is the one used by the computer??
Any help much appreciated.
Thanks.
rigsby,
There is much to read on the subject of a jerky, rough running M5 when cold. It is a very common problem on many M5s. Using the "sport" mode right away helps many cars, mine included.
I believe the "problem" is due to the way BMW have programmed the car. It is designed to run very rich when cold to protect the very expensive S62 engine. This rich condition is the main cause of the rough running. Using sport mode employs a different ECU mapping that is more aggressive, which probably makes more efficient use of the "rich" conditions when the engine is cold. This is probably why it feels better in sport mode when the car is cold.
JMHO.
Salty.
__________________
2000 M5 Avus Blue
Interior: titanium trim, Motorsport tri-color fabric seat & door panels w/ black leather, split folding rear seats w/ ski bag, sunshades, alcantara, DSP, etc, etc.
Mods:
- stock 2003 angel eyes upgrade
- Supersprint Magnum exhaust and X-pipe
- Rogue Engineering tranny mounts
- hardwired Valentine One.
- DME upgrade Sept 08.
- Red Line 70W80 tranny fluid
- door mounted cup holders
The tempsensor on the water pipe is for the electric cooling fan.
Implausible Temp error might be the IAT mounted on the left MAF, you could test swapping MAF's left-right and see if the Implausible Temp error goes away. Both MAF's have the IAT tempsensor but only the one on the left MAF is connected/used.
There is much to read on the subject of a jerky, rough running M5 when cold. It is a very common problem on many M5s. Using the "sport" mode right away helps many cars, mine included.
I believe the "problem" is due to the way BMW have programmed the car. It is designed to run very rich when cold to protect the very expensive S62 engine. This rich condition is the main cause of the rough running. Using sport mode employs a different ECU mapping that is more aggressive, which probably makes more efficient use of the "rich" conditions when the engine is cold. This is probably why it feels better in sport mode when the car is cold.
JMHO.
Salty.
The only problem is this condition has gradually got worse, it wasnt nearly as bad when I first got the car 3 years ago. I guess it could be some other fault which is exacerbated when cold running condition
Linear Mode
