97 540i just purchased, temp gauge pinned at hot

[Rb20s13]

Hello, just snagged my 162k mile 6spd 540 for $2800! Guy said he replaced timing guides at his shop 10k miles ago. Car was his daily for 5 years, let it sit for a couple of months. He drove the car 1hr to meet me, and I drove it 1hr back. The car was throwing a faulty temp sensor code, cyl 6 misfire, knock sensor. Car was at operating temp when I started it, began driving and it started getting up in temp. Outside temp was about 48f, car has a single 16in e-fan that PO had jumpered in order to drive it to me (he said it wasn’t turning on once it got up to temp, he pulled over and jumpered it for the drive). Was in 6th gear around 2k for the hour drive. Car was either in the red or just barely out of it the whole time. Would drop to about the 3/4 mark when I’d put it in neutral to let it coast. Any thoughts on what’s causing it? Engine bay wasn’t hot, my ob2 scanner red a peak ECT temp of 258f and a usual temp of 248f. Genuinely don’t think it was that hot, no boil over or bubbling when I stopped, felt pretty good temp wise to my hands. Any help is appreciated.

PS. PO said new WP recently installed
ran like crap under 2k rpm, temp would shoot up going up a hill in 6th even with slight throttle input.

[BMW540san]

I'm sorry to be negative and pessimist but that guy "said" he did this and that but how about some receipts for the work claimed?
Did you get any with the car?
I trully hope I'm wrong but if that temp. is correct...
Also, jumpering fan to constantly run?
I really see here all kinds of red flags.
First thing I'd do would be to check coolant level while cold and do the bleeding procedure.

[Rb20s13]

I agree, for the price I can’t complain, but it seems like there’s a good bit he didn’t disclose. No receipts on work unfortunately. Only thing that concerns me is what the obd temp was saying

[ross1]

I'm really curious as to why you would drive an ostensibly overheating car for an hour.
Let us know when you find an engine cheaper than a tow.

[BMW540san]

I agree, for the price I can’t complain, but it seems like there’s a good bit he didn’t disclose. No receipts on work unfortunately. Only thing that concerns me is what the obd temp was saying

I could argue that you actually overpaid considering what we know about the car at this point but let's put that to side and try to help you.
You really need to find out the state of engine before even trying to start it again.
Since the real concern here is overheating, did you check the condition of oil? Hopefully it isn't looking like milk shake and I'd go ahead and pull of the plugs and post a close up picture of them here.

[Rb20s13]

Oil is fine, little dark, but will change it tomorrow. No coolant smell the whole drive, heat blew warm through the footwell vents only, too vents were kind of cold. Could be thermo based off that alone.

[MtnGn]

[BimmerBreaker]

Sounds like you possibly drove it with an air pocket in the cooling system for an extended period of time. That would explain why the engine was hot but the top air vents were blowing cold

A thermostat will not cause an overheating condition unless it's stuck shut, if it is stuck shut, it would have gone nuclear after a few minutes in the red because a stuck thermostat would prevent cold coolant from the radiator from entering the engine.

258F is 125C, about 40F/20C too hot. I'm not sure why you just assumed this was ok and kept driving. It is possible the temp sensor was faulty, but normally this would present as it being pegged in the red, not fluctuating following driving conditions (going to 3/4 when coasting as described). This seems to me to possibly have been a "coolant temp sensor out of range" type code rather than "faulty" code... I imagine the temp sensor was in an air pocket instead of being submerged in coolant, thus the higher reading. Maybe you'll get lucky and a good bleed will sort it out. Maybe you'll be hunting for a new engine. Maybe there is something else going on altogether...

[BMW540san]

Oil is fine, little dark, but will change it tomorrow. No coolant smell the whole drive, heat blew warm through the footwell vents only, too vents were kind of cold. Could be thermo based off that alone.

Good.
BimmerBreaker expanded on what was my first assumption and he gives a good explanation.
You just might get lucky and if you do and engine is still OK, assume that everything PO claimed was replaced is probably hogwash.
Maybe he did replace WP but never bled it or bled it correctly which would explain your episode.

[Rb20s13]

Thank you for the advice man, I appreciate it. This was supposed to be a hold-me-over driver until I finish building my rb. Good news is m62 is very cheap.