[mojoman]

Ok, so here's what happens: Drive the car at 40-80 mph for about 1/2 hour... Oil temp gauge rises steadily to around 225 (higher than the usual 210)... the engine starts to loose power quickly like it is running out of gas.. I pull over and let it cool down for about 20mins, and then the same thing again... HERE'S THE WEIRD PART... when I turn off my lights, the Oil temo gauge rops to normal and the car runs fine...
ps> I recently had the alternator rebuilt.....and replaced the head.
any ideas?...

thanks
rick, nyc, usa

 

[Stevie]

Ok, so here's what happens: Drive the car at 40-80 mph for about 1/2 hour... Oil temp gauge rises steadily to around 225 (higher than the usual 210)... the engine starts to loose power quickly like it is running out of gas.. I pull over and let it cool down for about 20mins, and then the same thing again... HERE'S THE WEIRD PART... when I turn off my lights, the Oil temo gauge rops to normal and the car runs fine...
ps> I recently had the alternator rebuilt.....and replaced the head.
any ideas?...

thanks
rick, nyc, usa

Fuel pump dying? Lean mixture would explain the high temp reading.

 

[mojoman]

Fuel pump dying? Lean mixture would explain the high temp reading.

mmm..pump?.. not sure.. but the car runs perfect until it reaches 225 degrees..
i just took it for a ride cold, turned on the lights and the Oil Temp gauge jumped 20 degrees.....

 

[bobz]

mmm..pump?.. not sure.. but the car runs perfect until it reaches 225 degrees..
i just took it for a ride cold, turned on the lights and the Oil Temp gauge jumped 20 degrees.....

As a completely outside guess, you have a short in your oil temp guage circut which sends the car into limp home mode as not to damage the engine.
Have that checked out before anything else.

BobZ

 

[mojoman]

As a completely outside guess, you have a short in your oil temp guage circut which sends the car into limp home mode as not to damage the engine.
Have that checked out before anything else.

BobZ

That makes total sense to me.... but, i didn't know the M5 had "limp mode"!

thanks
rick

 

[bobz]

That makes total sense to me.... but, i didn't know the M5 had "limp mode"!

thanks
rick

The E32 has had a limp home mode sience 86 for the 750i's, so I can't see why not for ours?

BobZ