Author Topic: M44 in E30 - Issues... (Read 31202 times)

Royalratch · « **on:** September 13, 2007, 04:38:18 AM »

Hello from London.

I have an E30 Touring (The station wagon version). I recently dropped in a 2000 Z3 1.9L M44. It's great but has a one issue.

The M44 has one engine temp sensor that feeds all necessary clocks in any E36/Z3. The M42 in an E30 has multiple temp feeds which is where my problem starts. My M44 has one temp feed but my clocks need 2. Can I drill a new area for a temp sensor in the M44 head? Can I split the one existing sensor feed into two? My temp gauage basically shows misleading 'cold' info and is also very erratic.

You may like to know that M44's drop right in, you may need the odd pulley from an M42 and you'll need the M42 ECU (re-mapped to suit larger capacity etc) as M44 ECU's usually have all that BMW EWS security madness in them.
It's definitely smoother and much torquier down low than my stock 318iS Coup�.

Any thoughts would be great - thanks all.

gearheadE30 · « **Reply #1 on:** September 13, 2007, 04:43:25 PM »

As in clocks, do you mean one for the OBC and one for the cluster? If so, the OBC temp comes from a sensor mounted in the driver's side brake duct. I'm not sure how to wire up the engine temp, but if both readouts are for engine temp, it would probably be okay to just split the lead.

johna · « **Reply #2 on:** September 14, 2007, 03:32:52 AM »

I believe "clocks" is a British term for instruments or gauges.

tim_s · « **Reply #3 on:** September 14, 2007, 04:12:55 AM »

indeed! why not just use the existing double temp sensor - it has two feeds iirc? Mb your installer just used the e30 temp switch in the m44 head (m44 temp switch with m42 loom will require loom work)?

Royalratch · « **Reply #4 on:** September 14, 2007, 09:14:45 AM »

Quote from: tim_s;33675

indeed! why not just use the existing double temp sensor - it has two feeds iirc? Mb your installer just used the e30 temp switch in the m44 head (m44 temp switch with m42 loom will require loom work)?

That's probably what he did - there must have been a reason why he didn't do what you suggestd tho. Clocks means Speedo clocks - guages.

Can anyone confirm what part(s) I would need? I could probably do this the tweak myself if the engine doesn't have to come out.

Royalratch · « **Reply #5 on:** September 14, 2007, 04:05:49 PM »

Quote from: tim_s;33675

indeed! why not just use the existing double temp sensor - it has two feeds iirc? Mb your installer just used the e30 temp switch in the m44 head (m44 temp switch with m42 loom will require loom work)?

But it's an M44 loom that just goes into the C101 plug at in the bulkhead?
He did mention something about not using the M44 loom as it has all the EWS immobiliser / secuirty stuff in it.

D. Clay · « **Reply #6 on:** September 14, 2007, 07:56:27 PM »

I would "T" the existing port in the head as the sensors are different and it's hard to drill into the head and get all of the metal shavings out with it still on the car. I accidentally switched the temp sensors for the ECU and the temperature gauge. It caused the "Check Engine" light to come on and the temperature gauge to read very low.

Royalratch · « **Reply #7 on:** September 22, 2007, 04:13:24 PM »

That's what I thought the simplest thing to do would be. But do the 2 temp sensors have different signals / resistance ratings? Would a split signal cause the relevant instruments confusion?

Mt temp guage is schizo at the moment, when it's not showing 'just warm' after hours of use...

robweenerpi · « **Reply #8 on:** September 26, 2007, 10:27:36 PM »

The readings would be slightly off/slower response but as long as it's filled with fluid and not an air bubble they will conduct the heat energy to the sensors.

strypt · « **Reply #9 on:** October 19, 2007, 05:28:07 PM »

I run a M44 in my 318is E30 and I use the M42 E30 wiring and just put one of the sensors in the water pipe just under the head. One of the sensors are for the ECU and the other one is for the instrument cluster, and I do believe they have different signals as one sensor has two pins and the other one only has one. The water in the pipe is not as hot as in the head ofc and I put the sensor for the temp gauge in there so that the ECU would get the right reading in the head.

Royalratch · « **Reply #10 on:** November 05, 2007, 11:48:31 AM »

At the moment it has temps sensor pluged and sealed into the thermostat housing (looks ugly tho) and the other for ECU.

tim_s, the switch you're talking about definitely works? D.Clay above says the two signals are different so just splitting the signal or using double temp switch wouldn't work right?

D. Clay · « **Reply #11 on:** November 05, 2007, 04:59:03 PM »

These are the two temp sensors I accidentally switched. This is US M42.

06 ENGINE COOLANT TEMP SENSOR 1-POL 12621710512 $17.52
07 GASKET RING A14X18-AL 07119963200 $0.22
08 TEMPERATURE SENSOR M12X1,5 13621709966 $32.36
09 GASKET RINGA12X15,5-AL 07119963130 $0.10
When switched, the engine did not run right, the check engine light came on, and the termperature gauge read very cool.

silent lucidity · « **Reply #12 on:** November 06, 2007, 03:59:48 AM »

I also have an m44 in my E30, and I have the same problem. I have one of the sensors in the existing port for the m42, and another one wired closer to the firewall behind the head. The gauge is a little off and it never reaches the mid point like it used to with the m42. However, the needle in the temp gauge rests right above "cool" which according to a temp gun is at normal operating temp. Now if the needle were to go to the middle I would know that the engine is too hot. If you can measure the heat from your engine and figure out where the needle is at that point, you can kind of get an estimate on what temp your engine is at. I didn't want to drill another hole, because it would be kind of hard since the motoris already in, so hopefully this is an easier way for you

P.S. I <3 the m44

Royalratch · « **Reply #13 on:** November 06, 2007, 04:19:49 AM »

Thanks for this guys - very useful.

Another thing I was thinking was to 'advance' the gauge needle to sit middle at regular operating temperature.

My main concern tho is to tidy up the bodged wiring in the bay - I hate it!

How do M44's feed guage & ECU when fitted in their regular E36/Z3 homes?

Royalratch · « **Reply #14 on:** November 06, 2007, 04:29:15 AM »

M44 Head - Number 7 is a double temp switch:

I see what tim_s meant now - taking two feeds from the M44 switch would require loom work.
Anyone know how much? Can't be too much I'd have thought...