As some of you know I'm in Germany...it's freaking cold here. I bought a '90 BMW 525I a couple weeks back to get me through winter and I'm very happy with it overall thus far, its in just about perfect condition mechanically and cosmetically, definitely doesn't feel like a 20 year old car.

So here's my problem (which goes back to it being freakin cold here) it won't get warm, no matter how long I have her running she just won't heat up according to the temp gauge (barely bumps off the top of the blue line) and the heat doesn't get warm, like at all, it feels like A/C blowing even after a 150KM trip with a 40K stretch at ~200KPH on the autobahn. Now obviously it's getting warm somewhere in the cooling system so what the hell could be causing this..anyone with any E34 525 background here?

 

I'm not familiar with BMW 525s in particular, but the usual suspects would be a broken or missing thermostat, or a modification of the hose routing such that pre-thermostat coolant is going to the radiator rather than being recirculated back into the engine. Either one is easy to detect and repair.

Do you know where in the system the sensor that drives the CLT gauge is located?

 

Wow. Sounds like absolutely no circulation through the heater core.

Depending on where the temp sensor is, that could explain the gauge problem as well. Sounds like someone purposely blocked it off (maybe core was leaking and soaking carpet...cheap bastards), as even no flow would still heat up a sensor setup like ours.

Squeeze heater core hoses to see if they are building pressure...will be equivalent to radiator hoses when car is hot.

 

No idea....there's so much going on under the hood of this damn car that with the limited time I've had time to look around I'm not sure where in the cooling cycle the temp is taken from.

I can't believe I hadn't even thought about the heater core being bypassed, guess the fact that a colonel owned the car before me made me throw thoughts of cheap-o fixes out the window, I'll check that tomorrow for sure, starting to get tired of sitting in a cold car, lol.

Only thing making me think it's not a heater core problem is something I guess I kinda left out in my OP, the defrost will get just a little warm, like JUST enough to justify having it on, but still cold by my definition, switch it to defrost and blowing on my face or feet and nothing changes w/ the defrost BUT the other air is ICE cold.

I'm going to be pissed if I have to end up taking this thing to a German BMW dealer, but I think I'll resort to that if I can't get this sorted out in the next week or so.

 

In some automobiles, the flow of water through the heater core is regulated by a valve.

In others, the selection of hot air from the heater core vs. cold air direct from the intake is made with movable flappers. In many of these cases, these flappers are actuated not by a mechanical rod, but by an electric motor.

Neither one really explains the lack of a reading on the CLT gauge, so far as I can think.

Once you've inspected the heater core to ensure it's connected, pop the thermostat out of its housing. Make sure it's fully closed when at ambient temperature.

 

Will do Joe, thanks a lot, the 12 degree temps and winds while working on her don't exactly make for ideal conditions to diagnose problems mentally . I guess as cold as it is the thermostat being stuck partially open is a good guess since it is so cold and these things were designed to funnel as much air as possible through the radiator.

 

Soooo...all those problems have been fixed/disappeared. Now I have a new one, I turn the key in the driver's door and everything unlocks as normal except the driver's side door. The "peg" on the inside moves like it's trying to come up but can't go far enough. I crawled through the pass. side and attempted to unlock the door by hand.. No dice, she won't budge at all, tried pulling ont he handle and pulling up the "peg" pulling on the outside handle and pulling up, tapping the lock while turning it, can't get it to budge at all.

I'm really getting tired of crawling through the passenger's side already so any advice would be appreciated. Using the lock cylinder on the pass. door nets the same results. Any idea on how to remove the door panel without being able to open the door so I can check out the linkage/solenoid?

I know asking here isn't going ot get me the best results, I've posted on Bimmer forums as well but they all pretty much suck fat dick so I have little hope of getting any useful information off of them.

 

Door lock actuator. Its actually a motorized solenoid. little black box 1x2x3 with electrical that straps onto the side of the lock mechnizsm inside the door.

Gotta tear the door down to the to the lock actuator, but 90% likley its getting tired...

 

Any idea how I can tear the door down without being able to open it?