M30 engine ECU learning

[Annddrriy]

Changed ECU from 1989 Year to original ECU 1990 engine not starting sometime starts and RPM goes down and engine shut down. Another think out side temperature gage on dashboard shows -27°C when put old ECU from 1989 back on engine ECU all working good ?

[shogun]

The outside temperature sensor has no effect on the engine management and ECU. The ECU uses for the engine management the temperature of coolant sensor and air temperature in the air flow sensor of the intake system.

The temperature for outside air displayed on the OBC and in the check control of the cluster and the warning are for info only.
OBC training manual says in section temperature: Temperature button = indicates the outside temperature, If the temperature is below = 37 degree F. display will switch over to "temp" = 37 degree F. for 8 seconds (flashing display) + gong, and stay in temperature mode until removed.
The alarm will reset when the temperature increased to + 42 degree C.
Temperature display is dampened to rise slowly as vehicle slows to stop. This prevents engine heat from influencing reading the temperature. Restarts when vehicle speed exceeds 11 MPH.

Maybe something wrong with the other ECU, example for repair transistor http://www.e38.org/e28/louielouie/dme_fix.html

[Annddrriy]

Engine management and ECU It has effect from ambient sensor depends on weather condition outside it pick up signal from ambient sensor than take action what to do with firing order if MAF sensor gives signal its just cold around +4 C outside and same time ambient gives signal to ECU its -27 C than ECU gets error and engine no start and don't know what to do with fueling system add more fuel or add less fuel it works like a MAF sensor makes confuse. At this point I should wait for 10mn to see if temperature from -27 C will go down a bit if does than engine could start. That ECU was seating at garage for a five month and today I wanted warm it up but no luck.

[Annddrriy]

The coolant temperature sensor for the cluster gage and another one is engine temperature sensor in my car one sensor is blue plug and another one is black. Seems to me black connector is engine temperature sensor those two sensors also working with ECU. Yes may be need to re-solder transistors.

[shogun]

You are talking about a different temperature sensor. I am talking about the outside air temperature next to the fog light and I described the function above, and that is shown in the cluster.

The other temperature sensor you are talking about for the ECU does not show temperatures in the cluster, that is the ATS for the engine management:
ATS
The ATS is mounted in the AFS inlet tract and measures the air temperature before it enters the inlet manifold. Because the density of air varies in inverse proportion to the temperature, the ATS signal allows more accurate assessment of the volume of air entering the engine. However, the ATS has only a minor correcting.
The open circuit supply to the sensor is at a 5.0 volt reference level and the earth path is through the AFS earth return circuit. The ATS operates on the NTC principle. A variable voltage signal is returned to the ECU based upon the air temperature. This signal is approximately 2.0 to 3.0 volts at an ambient temperature of 20° C and reduces to about 1.5 volt as the temperature rises to around 40° C.

Here are all the details
http://opel-scanner.com/files/DME_1.1_1.3.pdf

Coolant temperature sensors CTS: in case your car has no EML, you have 2 sensors, one is for the temperature indicator in the cluster and has no effect on ECU, the other one is for the ECU
CTS
The CTS is immersed in the coolant system and contains a variable resistance that operates on the NTC principle. When the engine is cold, the resistance is quite high. Once the engine is started and begins to warm-up, the coolant becomes hotter and this causes a change in the CTS resistance. As the CTS becomes hotter, the resistance of the CTS reduces (NTC principle) and this returns a variable voltage signal to the ECU based upon the coolant temperature.
The open circuit supply to the sensor is at a 5.0 volt reference level and this voltage reduces to a value that depends upon the resistance of the CTS resistance. Normal operating temperature is usually from 80° to 100° C.
The ECU uses the CTS signal as a main correction factor when calculating ignition timing and injection duration.

Testing data for the sensors http://www.e32-schrauber.de/bmw/s-tempsensor.htm
blue for temperature indicator NTC 2,5 kOhm, the sensor for outside temperature for the OBC and check control is different 6.2 kOhm and the one for aircon near the blower motor is again different.
The blue plug and the other black one for coolant are different.
http://bmwfans.info/parts-catalog/E3...ostat_housing/
12 Engine coolant temp sensor 2-pol 12621710535 black
14 Temperature sensor 13621709966 blue M12x1.5
16 mperature sensor, water for EML cars, 12621288158

[Annddrriy]

Yes I am talking also about that sensor near passenger side of the fog light. When I put original ECU from car 1990 that ECU get a problem to start the engine but was working before no problem and on OBD screen shows -27 C. When I put back on not original ECU from 1989 all work good. Could solder connection crack after ECU seating for 5 month ?

[shogun]

Maybe something wrong with the long time stored ECU/DME, contact problems due to oxidation, cold solder joints, other components in there, probably also capacitors (?).
In the E31 forum they are discussing problems with the EML module, dead capacitors have to be replaced, I assume same with the DME, but there I have no details. You have to check DIY and find the faults.

[Annddrriy]

I would like to buy bmw GT1 scanner this scanner give more information than bmw carsoft. Do you know where to buy and what kind GT1 scanner is better ?

[shogun]

One of my wrenching friends bought such a GT1 clone from China, very bad quality, he never got it running and scrapped it. Maybe you ask here in the software forum.

[Annddrriy]

Someone recommend me long time ago to buy original BMW GT1 it will work good.

[Annddrriy]

Who could send me software instructions with the link how to remap ECU cam shaft identification sensor from cylinder #6 to cylinder number one because that port of #6 a bit weak of the age not giving correct signal to ECU ? Also cylinder number 1 ignition wire is much shorter than cylinder number 6 of number one will through signal faster than through long wire. The simple solution just put it cam shaft identification sensor from cylinder 6 wire to number 1 ignition wire without remapping anything.

[shogun]

Who could send me software instructions with the link how to remap ECU cam shaft identification sensor from cylinder #6 to cylinder number one because that port of #6 a bit weak of the age not giving correct signal to ECU ? Also cylinder number 1 ignition wire is much shorter than cylinder number 6 of number one will through signal faster than through long wire. The simple solution just put it cam shaft identification sensor from cylinder 6 wire to number 1 ignition wire without remapping anything.

Do not make it too complicated, for that you would have to contact a chip tuner which knows his business very well, probably no one has ever done that before. And it costs for sure more. Will be cheaper, easier + less troublesome if you fix cylinder #6. These engines are running in this design since >40 years. You mentioned in another thread that you made your ignition wires DIY, so make a new one for #6, buy new quality cylinder identification sensor + add that. Maybe also new distributor, rotor + ignition coil. I have read on another forum that some aftermarket ignition wires had a too thick insulation and the donut could not pick up a clear signal. Also weak sparks from an old ignition coil can cause this problem.

[Annddrriy]

M30 Engine runs two pistons at the time for an example #1 and #6 at Top Dead Center and so on next same 2-5 and 3-4 by 3 sections by firing order 1-5-3-6-2-4. Will it makes any difference if donut will be on any other cylinders except #6 and #4 ?

[Cactuar]

If you'd like to start over with a good set of spark plug wires, including the #6 ID wire, you can order BMW part # 12120407868.

It fits the M30B35 engine but it's much cheaper than the usual listing from BMW.

[Annddrriy]

Ok thanks. Did you try those wires on your BMW ? How much cost $ ?

[Cactuar]

Around 100 USD. theBMWbeast installed them on a Dinan 535i with the M30. https://www.bimmerforums.com/forum/s...6#post30742086

[Annddrriy]

This is good deal $100 last time I pay $160 for a wire set brand bremi did not change anything the engine remain running with misfiring as it is before. I already ordered wire by foot I get 6 miters going to cut same size to cylinder wire #6 this it the longest wire with donut sensor. 7mm solid copper core spark plug ignition wire sold by the foot. I would like to check wire set on my bmw with oscilloscope that toll would tell what wire not firing good.

[shogun]

ignition wire length does not matter, see workshop manual, ignition wires have approx. 0 ohm. The attached plugs/boots make the difference in ohm, the plug going to the spark plug has the highest ohm.
Test your system in detail.
M30/M70 ignition system data accdg to Bentley
Coil primary, coil code # 2051118335 terminals 1 (-) and 15 (+) resistance 0.50 ohm, Coil primary, coil code # 20510171101 terminals 1 (-) and 15 (+) resistance 0.37 ohm
Coil secondary, coil code # 2051118335 terminals 15 (+) and 4 (ctr. resistance 6.0 kohm, Coil secondary, coil code # 20510171101 terminals 15 (+) and 4 (ctr. resistance 9.0 kohm
spark plug ends 5.0+/- 10% kohm, shielded plugs 1.0 +/- 20% kohm, spark plug wires 0 ohm (approx.), rotor 1.1 +/- 10% kohm
crankshaft position/rpm sensor: 540+/- 10% ohm

from workshop manual
distributor rotor 1+/-20% kohm, angled/shielded connectors 1+/- 20% kohm, spark plug connectors 5+/- 20% kohm, cylinder identification sender coil resistance at 20 degree C (68F) <1 ohm, pulse sender/crankshaft position sensor coil resistance 540 +/- 10% ohm, Donut/ cylinder identification M70, S70: Resistance at 3-pin connector. Measure plug between pin 1 + 2, ≤1 ohm, insulation resistance between pin 2 + 3: ≥ 10 MOhm, temperature switch for e-box cooling E32 750: switch on at 44 +/- 3 degree C, switch off at 36 +/- 3 degree C.

did you ever check the fuel tank breather valve?
the fuel vapors are fed to the engine through an activated carbon filter with the addition of fresh air. in the line from the carbon filter to the air MAF is a valve that regulates the venting flow depending on the operating condition. the valve is cycled depending on the engine speed and load. the cycle has 16 steps and starts when the lambda probe is active. at the end of a cycle the valve closes for 5 minutes. without 12V condition ( de-energized) the valve is closed by a check valve. when the vacuum in the MAF rises, the valve is opened as long as there is no 12 volt voltage.
for a short test:
The tank vent valve should have a resistance of 45 ± 20 Ohm and should be closed when de-energized.

[whiskychaser]

Who could send me software instructions with the link how to remap ECU cam shaft identification sensor from cylinder #6 to cylinder number one because that port of #6 a bit weak of the age not giving correct signal to ECU ?

The engine will run without that sensor. If you suspect a faulty plug lead, run the engine then disconnect one lead at a time. Make sure you insulate yourself to avoid getting a shock. Look for arcing and evidence of tracking

[shogun]

yes, it will run without the donut, the German test instructions from BMW says for the M30 engine:
am Stecker des Impulsgebers betraegt der Widerstand der Spule 0.2 - 1 ohm bei 23 plus/minus 5 degree C. Einspritzarten:
Halbsequentielle Einspritzung
Ab einer Drehzahl von 600-800 RPM wird nur einmal pro 720 Grad Kurbelwinkel in einer Zylindergruppe (2-4-6 oder 1-3-5) eingespritzt. Diese Steuerung kann nur arbeiten, wenn das DME Steuergeraet vom Cylinder Erkennungsgeber (donut) an der Zuendleitung 6 ein Signal empfaengt.

Parallel Einspritzung
bedeutet gleichzeitige Ansteuerung aller Einspritzventile pro Kurbelwellenumdrehung und erfolgt nur, wenn der Zylinder Erkennungsgeber (donut) kein Signal liefert.

Kaltstartsteuerung
zu Beginn der Startphase wird bis zu 5 Kurbelwellenumdrehungen jeweils 3 x pro Zylindergruppe eine erhoehte Kraftstoffmenge eingespritzt. Diese ist abhaengig von der Motortemperatur. Waehrend der Startphase erfolgt temperatur - und drehzahlabhaengig eine Reduzierung der Anfangs - Einspritzmenge, um einer Ueberfettung vorzubeugen. Bei wiederholtem Start innerhalb einer Minute wird nicht mehr die volle Start Einspritzmenge zugeteilt. Nach dem Start (ab circa 600 RPM) erfolgt die Einspritzung nur noch 1 mal pro Kurbelwellenumdrehung, je Zylindergruppe. Dies bedeutet, dass bei der ersten Umdrehung in die Zylinder 2,4,6 und bei der zweiten Umdrehung in die Zylinder 1,3,5 eingespritzt wird.
In der Warmlaufphase bis 70 Grad Celsius Motortemperatur werden ebenfalls drehzahl - und temperaturabhaengig die Einspritzzeiten entsprechend verlaengert. Die Werte sind fest im Steuergeraet programmiert.

=================
at the cylinder identification sensor, the resistance of the coil is 0.2 - 1 ohm at 23 plus/minus 5 degrees C.

Injection modes:

Semi-sequential injection
Starting at 600-800 RPM, injection occurs only once per 720 degrees of crank angle in a cylinder group (2-4-6 or 1-3-5). This control can only work if the DME control unit receives a signal from the cylinder detection sensor (donut) at the inlet end ignition wire 6.

Parallel injection
means simultaneous control of all injectors per crankshaft revolution and only occurs if the cylinder detection sensor (donut) does not supply a signal.

Cold start control
At the beginning of the starting phase, an increased quantity of fuel is injected 3 times per cylinder group up to 5 crankshaft revolutions. This depends on the engine temperature. During the start phase, the initial injection quantity is reduced depending on temperature and engine speed in order to prevent too fat mixture. In case of repeated start within one minute, the full start injection quantity is no longer allocated. After the start (from approx. 600 RPM) the injection takes place only 1 time per crankshaft revolution, per cylinder group. This means that at the first revolution, injection takes place into cylinders 2,4,6 and at the second revolution, into cylinders 1,3,5.
In the warm-up phase up to 70 degrees Celsius engine temperature, the injection times are also extended accordingly, depending on the speed and temperature. The values are permanently programmed in the control unit.
=================
or simply said: Bill R. aka Rainman once upon the time said: Winfred is talking about the sensor on the plug wire that controls the sequencing of the injection not the crank position sensor...If the inductive sensor on the plug wire fails then it goes into gang firing as Winfred said, since the m30 is a semi sequential design meaning that it triggers the injectors in 2 banks of 3 every other revolution, when it goes into the gang fire as he calls it, then it triggers all six at the same time every revolution but decreases the volume of fuel by 50% .. And i would imagine that all six triggering at the same time would make a much louder noise...

[Annddrriy]

There is no any valve in the tank except check valve on output gas flow I have changed last 5 months ago car did not start when engine was hot. Another purge valve for ventilation system working good. There is another fuel regulator damper is on end of the fuel pump which is regulate fuel pressure for injectors. The purge valve working after engine warmed up when engine at starts up valve not working.

[Annddrriy]

Possibility the MAF hot wire sensor not working properly some guys posted about MAF sensor not working properly because it gives another number when ignition switch on the number should be at multimeter from 0.1v up to 1.04v its maximum if is exceeded that number the sensor is bad and nothing you can do about it in this option just change the sensor but sensor is not changeable you have to change complete unit that test was done on not BMW car it was WV car. Another guy talking about another number when ignition switch is on the number should be at multimeter from 0.25v and when engine is running the number should be 1.15v that test was done on BMW 735i E23.

[Annddrriy]

Air flow meters, hot wire or hot film mass air flow sensors directly measure air mass, as the convective qualities of air are affected by factors like temperature, humidity and density when weather becomes 0 C resistance number change. Hot wire sensors create an analog signal and hot film sensors a digital frequency signal. Hot-film MAF sensors function much like a hot wire sensor, and used a centrally-heated film or metallic grid-type element. One side of the film encounters cooling airflow, while the shielded backside maintains a consistent temperature, and the current differential between the two is measured and relayed as a square-wave digital frequency output, between around 30Hz at idle and 150Hz at wide-open throttle. Hot film sensors tend to be more robust and less susceptible to contamination than hot-wire types
How do you test a BMW MAF? with the engine at idle speed, gently tap the MAF sensor with the fingers of an open hand, if the engine stumbles or stalls, the MAF sensor is defective. An engine with a bad MAF sensor may be hard to start or stall after starting. I move flap a bit to open door the engine lower RPM and stop running is that sensor bad ?
s-l1600.jpg

[shogun]

your M30 engine does not have a MAF. You car has the older type AFM = air flow meter.

Air changes its density with temperature and pressure. In automotive applications, air density varies with the ambient temperature, altitude and the use of forced induction, which means that mass air flow sensors (MAF) are more appropriate than volumetric flow sensors (AFM) for determining the quantity of intake air in each cylinder.

AFM testing 11 minutes tutorial
Video tutorial on how to testing and troubleshoot a BMW air flow meter which is the design of an early style mass air flow sensor. This is a Bosch Motronic system and is also found on other vehicles besides BMW such as Alfa Romeo, Volkswagen, Porsche, Mazda, etc. Similar procedures may be applied to other vehicle, but refer to OEM specifications to ensure the values are the same. I also did two types of testing on the potentiometer which were done by both the resistance and applying voltage to the circuit. I would recommend doing the voltage test vs the resistance because it is a much more reliable test. The resistance test will always show the mildest of contact issues and magnify the readings. A faulty air flow meter can cause issues with starting, idle, fuel economy, throttle hesitation, throttle flat spots, and emissions. This particular tutorial was done on a 1984 BMW 733i equipped with a 3.2L inline 6 cylinder M30.
https://www.youtube.com/watch?v=hQYRep6K15k

AFM ADJUSTMENT TO CORRECT AIR/FUEL RATIO https://www.youtube.com/watch?v=yQukm7lNux4
M30 535i air flow meter testing and cleaning https://www.bmwfanatics.co.za/thread...leaning.69590/

Your M30 has the volume air flow meter (vane type) instead of the mass air flow meter used on the M70. Bentley says on page 130-13 with regards to vane type flow meter testing:
disconnect harness connector from AFM.
Using a digital voltmeter, test for voltage at terminal 3 in connector. With ignition on there should be approx. 5 volts.
Turn ignition off and remove intake air boot. Connect a digital ohmmeter across sensor terminals 2 and 3. Swing air flow sensor vane thru its range of travel. Resistance should change steadily without interruption.

Intake air temperature sensor testing:
Using a digital voltmeter test for voltage across terminals 1 and 4 in volume air flow sensor connector.
test temperature...........resistance k ohms
14 +/- 2 F (-10 +/- 1 C)..... 7-11.6
68 +/- 2 F (20 +/- 1C)..........2.1-2.9
178 +/-2 F (80 +/- 1 C)........0.27-0.40

TPS throttle position switch M30 engine without EML
test terminals automatic transmission
idle position 4 and 6
full throttle position 4 and 5
with ignition on, check for supply voltage (VDC) to switch. If voltage is not present, check wiring from ECM

DIY: BMW Air Flow Meter Refurbishment https://www.youtube.com/watch?v=Z-QlPtsjh7g&t=127s

[Annddrriy]

An air has leak after air flow meter through manifold purge valve does its work cause rough idle. Possible solution make to block manifold output hole to purge valve. Install vacuum gauge or block the hole with any plug. ECU counts extra air and adding more fuel making mixture reach for injectors to overflow.