I am having a time with my 1995 850. We first noticed the lighted arrow blinking off and on at tmes, and it appeared that the problem where the transmission gets stuck in winter mode was happening off and on. We had the switch replaced (the one that changes the tranmission mode) but it still did this. We put the old switch back on.

Then, we noticed the car getting smelling hot and then it began to show hot on the temp gauge, and losing coolant. Replaced the thermostat, this seemed to help with the temp gauge showing hot. However, I noticed that whenever the transmission issue was happening, the car would begin to smell hot, but the temp gauge never reads hot now. the car seemed to do fine on the highway, but problems seem to show when I am going around town - stopping and starting a lot.

So finally we found antifreeze in the tranny and trans oil in the radiator and the mechanic said to change out the radiator. We did, but now we are still having the problem where the car seems to have little power (but only at times) when starting to accelerate from a stop, and when this happens, you can open the hood and see the overflow tank popping and hissing and water coming out of it...so we have to add water/coolant. But the weird thing is that the temp gauge always stays normal. Sometimes, the transmission seems fine. But I have noticed a couple of times, when in traffic and going up a steep incline, that the overflow tank will be popping and hissing. It does seem that there is a connection between the car not being able to accelerate well, and losing coolant from being hot...but why isn't my temp gauge showing hot? It does seem to work right because I can watch it consistently start from cold, slowly go to mid level and stay in normal range.

I had a guy look at it and say he thinks that it has too much pressure...that the fan may not be coming on right...or maybe the waterpump is going bad? But how would this affect the power when I accelerate...and only some time?

BTW, when we ran the thing that gives error codes, the only thing that showed was the transmission mode switch...that's why we changed that out.

Thanks in advance!