Codes p117 and p1338, and red oil light on?

It actually had a lot of codes which are attached. I deleted all and restarted and immediately read it again and first one that came back aline was 2936 coolant temp sensor, electrical short circuit to ground. After a minute code 33fe cane back engine oil pressure control plausibility, statuc: pressure too low. Engine sounds normal. Also code oil pump: pressure too low 3406. I monitored the scanner data, and the ect engine coolant temperature was 123f after 2-3 minutes of starting. I also just noticed 5 minutes later that there is white smoke from exhaust. Water level is full. Oil is full.

Next start i got check engine light with code p117.

And the fan stays on after the engine is off. Car is not hot yet but i think the computer thinks it is.

There are a few TSBs about the temperature sensors being an issue on them.
BMW SI M17 02 13 being the latest one.
https://dot.report/bulletins/MC-10146802-9999.pdf
I would look into that and then see if it was completed.
The fans will also come on if the temperature sensor signal is missing. As you are showing the error of it being shorted to ground that would cause the DME to say, "I don't see a temperature signal, I better turn the cooling fans on to protect the engine" The temp sensor is a simple thermistor that varies in resistance as the temperature changes. On many cars you can unplug it and it will turn on the fans for the same reason. You say that it shows a warm engine in a few minutes, which would be normal. From that and the other codes I would start hunting on the wiring harness for damage first. Look at sharp corners or hot spots. If a few wires in the harness were shorting, you could get all this. The other possibility is a bad DME which is somewhat common on the minis. I would check the coolant sensor wiring first. Go into live data and watch the coolant temperature, then unplug the sensor. See if the temperature changes.

Good ideas, thanks. I also heard about oil getting into some PCM or DME wires, I just never found out where per the conversations I read.

Yeah, oil migration is a thing for sure. I've seen it with transmission connectors and a few throttle bodies where the seals were junk from the day they were installed.

I am almost finished changing the thermostat assembly. Also checked the back to see if there is any leak in the back sensor which the other code shows which has to do with another TSB, i think. I don't know what it's called, but there is a harness that goes into a circular thing in the block and has one screw, the harness goes inside. TSB says to remove it and update it. But there is hardly any leak from it. Code 2DA0 points to one of the can sensors. Can you tell me where it's located so i can remove it and clean it first?

The 2DA0 code is the same as a crank-cam correlation code in any other make but you mentioned a P1338 earlier. That would be a circuit code to the sensor, showing it shorted high. That would also set the other code. The sensor is on the top rear of the head in the middle of the cams.

I think i see it on the back of the head under the valve cover kind of, on passenger side. Can i replace it with the exhaust one to see if the code comes back? Where is the exhaust one?

They should be next to each other if the service info on that engine is correct. They are the same sensor.

Removed back one first and it had dirt on it, same for front, cleaned both, one sound louder than the other, but applying voltage to both they did click. Also replacing the oil pressure sensor.

Not good to see that much debris in the oil. Might need to do a few rapid oil changes to get that out.

New thermostat and harness. New oil pressure sensor, new oil filter and oil. Started car and light for oil pressure immediately comes on and all types of codes. The engine is smooth. The fan still came on and same p117 code. Delete it and fan stops. No oil in the dme connectors sitting on top if engine on driver side. Other codes that set are below. Decided ti leave it for fee and then do a motor flush. Added it to the motor. Started the car and there was no red light and no check engine light came on. Strange. Left it running 5 minutes and now going to change the oil again and see. But there are no codes after running the motor flush in it only the p117 pending. Even when the engine is off and the ignition on fan stays on then i delete the code and it stops then 3 seconds later comes on then i delete the code and it comes back on.

Looked at live data and it shows ect at 285, but it's not overheating of course but that's why the fan stays on.

Okay, with live data up, unplug it. Does it change to -40 or what? With it unplugged short the two terminals what shows then?

Have not thought about that, yup, let me try it.

First picture you provided shows an insulation part or something. Why are they using that? I only replaced the whole thermostat assembly. I assume the sensor that cane with it is what reads the ECT correct? I think it has 2 connectors. I am guessing one is the sensor, and the other is to read thermostat?

If they are, they both connect then run to a bigger connector at main harness on two of them. I guess i can just unplug that and see if the temperature changes at all. And to short it I will plug it back and just remove the sensor harness and not the thermostat harness.

Remived the connector that sends wires to thermostat and to the sensor, temperature did not change on the scanner. Stayed at 64f. If it doesn't work, then how is it that i read 285 once?

If DME is bad is that the one on top by reservoir? The n driver side?.

After replacing the pct which is on top of the valve cover, which has the sorting and diaphragm I started the car and it smoked like crazy, hard to say if blue or white. coolant and engine oil full. Left it running 15 minutes then it cleared. No red oil light came on. Then I started it this morning and no light was on then took it on a drive and was fine. Got into my driveway and parked and it threw the smoke puff again, again not able to see whether its white or blue.... then goes away after a while, could be valve stems, strange on 90k, I sold many of these without issues of smoke. Have flushed the motor before then installed a new filter and fresh oil. Then after a while red light came back. It only does at low RPMs, goes sway soon as I hit the throttle.

Sounds like that engine has a few issues. The oil light at low rpm could be worn bearings or a bad pump. The puff of smoke could be valve seals but if this is a turbo engine I'd look at the seals in it as well. I would toss a mechanical oil pressure gauge on it to test the real oil pressure as well. If you get a real pressure that drops off at idle it's likely not worth doing much on that engine.

Yes, i thought so too. I thought about the turbo but there was no way to tell without removing it. Too much headache. Putting an oil gauge on these is pain the behind. No room. Plus, you have to remove a bunch of stuff to get to it and then if you want to run the car you have to put it all back and that won't leave room for the gauge. It's not worth doing anything to it unless someone wants to spend time and remove the oil pan and look. Even if the oil pick up is clogged up, the smoke is another story.

True, they are not a lot of fun to work on but the light being on at idle sounds like low pressure. I know that the times I see that on a car with a turbo I question the owner about maintenance. 90K isn't that much but if they were doing oil changes every 10K it could have chewed the bearings out of it. Especially if it was owned by someone who thought a cold air kit was a good idea.

car is strange. I changed the PCV diaphragm. Anytime I start it either ton of white smoke from exhaust for a while, or bluish when left idling for an hour. No antifreeze smell. Sometimes I start it and there is zero smoke. Oil is clean. Oil pressure light doesn't always come on. I will check the connector again. How does the light work? Does it have 2 pins and jumping it can confirm all is working from ECU is light does not come on? I want to make sure if it is a pressure issue or a ppm issue.

It has 3 wires. Power Ground and Signal to the ECM. White is Ground, blue is power, and yellow is the sensor signal to the ECM.

So help me understand. When the pressure is normal the sensor wires are grounded? And when it senses low or high oil pressure signal is sent out and the ground gets cancelled?

I tested the wires with ignition on and all show power (+).

I disconnected and started the car and there is no code for it yet.

It is strange. Car is super powerful, no misfires or any loss of power but driving it, it's a puff of continuous smoke.

The sensor is a variable resistance that changes the output voltage on the sense feed. One should be a ground; one should be power and the last should change as the oil pressure changes. It isn't a simple On Off style switch.

All of them have power, none have ground. Ugh

White should be a ground, blue wire should be power. The yellow should vary with oil pressure.

Yes i know. But I tested it with the probe and that is not the case. Every one of them has battery power, none are ground.

Then the ECU has a problem. I would look at the grounds to it to see if a bad ground is causing the problem.