Firstfives.org

Re: 79 528i 03/79 production date.
The Fuel injection temp sensor, I'm guessing is on the radiator. Correct?
Are these the correct numbers for testing?

14F(-10C) 8200-10500 ohms
68F(20C) 2200-2700 ohms
176F(80C) 300-360 ohms, fully warmed up

I have a poor running at low RPM when warm condition.

Sherman, the ECU temp sensor (I almost typed "DME" but we are dealing with L-Jet here) is on the thermostat housing. It is slightly buried, the sensor has a white plastic top where the harness connects (now prolly brown) and a 2 pin push on connector basicly like an injector connector (I don't have a pic right now). It is buried a bit down low but you can see it just fine. I don't have my nominal values handy but your numbers are prolly pretty close. BMW built a really nice harness to test these which nobody has any more. Let me know if you need a sensor, I have new in stock.

So, what happens if the temp sensor is not working any more? Does the car run rich?? My mechanic adjusted the three afm's that I have, using the info from Metric Mechanics info. It' still runs rich!!
Thanx for any info,,,,Greg

Yes, rich running is the result.

You should be able to disconnect it when it's warm and it'll run erratically.
That's what I'm thinking my warm engine low rpm rough idle is cause by.

I only wish there was a Bentley for these cars.

I don't know why I had to log in again. I wanted this to be a reply to your response.
Anyway, If, when I disconnect the temp sensor and it runs erractically, does this mean it's working? And it needs to be in the loop? I think that's what you meant. Just checkin'. BTW, is your name Sherman? Greg

Yep, Sherman it is.

s = sherman
+
watters = last name
+
sr = senior, as I have a namesake. the II (2nd)
=
swatterssr (username)

Ok, yes, when the engine is warm, erratic running when unplugged at idle means it's working, motor is getting too much fuel.

Thanx, Sherman. I'll never try to undercut your situation. Buy that new sensor. I say this because I believe I was taken advantage of in Beaverton, Oregon concerning the '81 for sale. I'll never blame Brandon, the seller, but!
My experiance with this board has been extremly positive except for this one situation. I may have gotten back-stabbed by someone on this website that I thought had a good rep. I say this 'cause he only responded to me saying that my email to him ended up in his junkmail file. He was recommended by Lars, who has a stellar rep. Then, I asked him to look into this car, and let me know what he finds. He never got back to me! Not even to tell me to go to hel*! Then I called Brandon, in Beaverton, and got no response. So, what would your gut feeling come up with? Like I said before, I'm not blaming Brandon, he wants to sell the car. But I, also wanted to buy the car! Anyway,, sorry for the rant. Greg

Sean, or whoever else wants to chime in;
Here's some pics of what I've got, please tell me if I'm right, correct where necessary and fill in any blanks for me.
My understanding is I need to check/change the sensor, #17, in the last photo, correct?

These first three are under my hood:

In this pic:
#1-The blueish/green is vacuum for the distributor?
#2- The brass colored single wired one is for the cluster temp gauge?




In this pic:
#3-The white one toward the front with the three holes but nothing plugged into it is for _____________?




This pic is of the E28 radiator upgrade I installed:
#4-Auxillary fan? or ___________?
#5- __________________?



Just for reference, this is the removed E12 radiator which had the same two sensors on the bottom by the hose port.



This link is to the photo from RealOEM.
Part #17 Temperature Sensor, Water is the one that sends the signal to the ECU to regulate fuel volume, depending on engine water temp, correct?
It's attached to the #03 Additional Air Slide Valve housing under the intake manifold on the driver's side of the engine.

GripGreg wrote:Thanx, Sherman. I'll never try to undercut your situation. Buy that new sensor. I say this because I believe I was taken advantage of in Beaverton, Oregon concerning the '81 for sale. I'll never blame Brandon, the seller, but!
My experiance with this board has been extremly positive except for this one situation. I may have gotten back-stabbed by someone on this website that I thought had a good rep. I say this 'cause he only responded to me saying that my email to him ended up in his junkmail file. He was recommended by Lars, who has a stellar rep. Then, I asked him to look into this car, and let me know what he finds. He never got back to me! Not even to tell me to go to hel*! Then I called Brandon, in Beaverton, and got no response. So, what would your gut feeling come up with? Like I said before, I'm not blaming Brandon, he wants to sell the car. But I, also wanted to buy the car! Anyway,, sorry for the rant. Greg

Not sure what this is about, but there is a 'Sticky' in the For Sale/Wanted for Buyer / Seller Feedback where this can be discussed and easily accessed by future users.
I think you should post your comment there.

No problems with your questions/comments in this thread as it only helps clarify for all interested in this Temp Sensor / ECU issue.

Sherman, interesting, the 79 is set up a bit differently, I forgot about that... You are pretty much spot on with the id's the 3 wire port at the forward edge of the head was for some long forgotton BMW test tool, possibly to check timing and RPM...

On your car with the water controlled idle valve on the mid drivers side of the engine, the ECU temp sensor is down there as in your diagram.

Techboy wrote:Sherman, interesting, the 79 is set up a bit differently, I forgot about that... You are pretty much spot on with the id's the 3 wire port at the forward edge of the head was for some long forgotton BMW test tool, possibly to check timing and RPM...

On your car with the water controlled idle valve on the mid drivers side of the engine, the ECU temp sensor is down there as in your diagram.

The two radiator sensors?
I'm sure one controls the auxiliary fan, how about the other?

High and Low Aux Fan, don't know what the switch in the lower neck is for, mine is disconnected also.

[quote="swatterssr"]:
#3-The white one toward the front with the three holes but nothing plugged into it is for _____________?
/quote]

This is a port to connect a diagnostics machine. It is missing the cap like alot of other cars....

alotawatts wrote:This is a port to connect a diagnostics machine. It is missing the cap like alot of other cars....

Any idea what diagnostics are retrievable or systems are diagnosed from this connection port?