Repair notes to keep your BMW M3 E30 running great!
WARNING: Porsche 928 oil filters
WARNING!!!!
Some in M3 SIG say that Porsche 928 oil filters can be used in M3. But, before you do it, read this:
I thought to try it out as well and in my opinion it doesn't work, here's why:
THREADS ARE DIFFERENT, see the pictures below:
First, Original M3 OEM filter. Thread is 3/4, about 19mm.
Then, Porsche filter has M20x1.5mm threads:
So, I would say there is a ig risk that the oil filter might pop out, especially with high rpms. You don't want that to happen...
"CarbTune" by BemariM3Ex
Hot to make a cheap tool to adjust throttle bodies
Since S14 has an intake track for each cylinder, it is important that the throttle bodies are in sync. Commercial tools exist and in fact I bought one, but was already broken when I received it. This is the tool I made:
Items needed:
- Small diameter transparent tube
- Painters stick
-Transparent packing tape
- Lightweight oil
How to do it:
- Take the tube and loop it around the stick as shown in the picture and secure it with tape
- Add oil into the tube
That’s there is to it.
Now remove the throttle body nipples between cylinders 1 and 2 and insert other end to cyl #1 and other to cyl #2. Then adjust the throttle body bypass screw until oil levels are the same both sides.
Repeat the same for cylinders 3 and 4.
BMW M3 E30 Dual Temperature switch replacement
Aux fan is controlled by a dual temperature switch which is located in the thermostat housing. Switch has two switches in it, slow speed is operated at 91C and fast speed at 99C. Code for the switch is 61311378073.
I had some doubts that my switch is not functioning correctly, so I ordered a new one. I tested the switch by heating it with a heat gun. For some reason it only worked at one speed. I compared the switches and switches look little bit different. I also tested both switches by measuring the resistance on the bench and this revealed why the new one worked only at one speed: Swiches were different, see following table how new one and old one compare. What makes it even more confusing is that ETM connector drawing, page (8500-3) is incorrect for the new switch:
These are the pictures in ETM:
This is how it should be:
Problem is that pins 1 and 2 are not in correct place in the connector drawing.
Next problem is that switches are different internally. See following table how switches operate:
|
Old Switch, continuity between |
New switch, continuity between | |
| Slow speed | Pins 3 and 2 | Pins 1 and 2 |
| Fast speed | Pins 3 and 1 | Pins 1 and 3 |
NOTE: Pin numbers are according to the corrected drawing.
So, in order to use the new switch, I had to swap pins 1 and 3 by opening the connector and swapping the pins. After swapping the pins both speeds worked fine.