M30 engine ECU learning

[Annddrriy]

735i/iL E32 M30/B35 (211hp) 89-92 0261200 179 Bosch Motronic M1.3

[shogun]

that the engine RPM drops below specification can also be a problem of the valve body. The solenoid for the converter lock up clutch is grounding out against the transmission case. Remove plug from transmission control unit and connect to universal adapter and measure resistance between pin 25 and vehicle ground as well as between pin 1 and vehicle ground http://www.europeantransmission.com/...Hvalvebody.pdf

ZF4HP22 EXTREMELY HARSH SHIFTS
complaint: Harsh engagements and severe shifts while all shift speeds are okay.
cause: Pressure Regulator “Force Motor” failure (See Figure 1). Extremely high pressure will result. This cannot always be diagnosed with an ohms test as the failure may be mechanical.
correction: Replace the Pressure Regulator “Force Motor”.
Note: A new Pressure Regulator from BMW is just under $600.00 and is usually available in less than two weeks. There is, however, a suitable alternative that has proved most effective. The G.M. 4L80-E Force Motor is manufactured by the same company and aside from a few minor differences does the same job. Most of the overall dimensions are the same except that the G.M. 4L80-E Force Motor uses screens in the plunger and port areas (See Figure 2). Those differences are insignificant. A new 4L80-E Force Motor will cost you about $133.00. The G.M. part # is 8677314
Pressure Regulator ohms test across both terminals should be 2.5 - 4.0 ohms resistance. This ohms test should be done near room temperature. Do not energize this force motor with full battery voltage as damage may result.
The BMW Pressure Regulator on the left uses no screens. The G.M. 4L80-E Force Motor on the right has screened ports and a steel ball pressed into the screw head to prevent tampering. http://www.europeantransmission.com/....BMW/92-23.pdf

[Annddrriy]

Yes that is what I was thinking about too but interesting why another ECU does't drop RPM to 300 before. But now also another ECU drop RPM to 300 when engine cold I shift a gear to drive after 2 minutes worm up engine one's I put gear and release brakes car moving forward and slow down and almost engine turn off and after two seconds return to run normal. The mechanic put it new pressure regulator solenoid and 3 shift solenoid from germany which was not available at that time. What kind shift solenoids he put it I don't know probably put it something else when gear shifted to reverse strong dull thud. Do you mean solenoid itself coil inside has short to ground or harness connector wire touching to valve body ?

[Annddrriy]

I will try to put low amp probe to engine ECU wire pin#1 timing control and coil terminal #1 black wire than after that checked ECU #pin 27 to coil #15 to see on oscilloscope wave pattern if is ECU working properly. I am going to put oil pressure gauge on torque converter before I hook up oscilloscope if pressure low at idle 10psi in forward gear no sense to check with oscilloscope. Also could check line pressure solenoid with scope trace at idle if voltage not drop or very high when gear selector is set to position drive.

[shogun]

Do you mean solenoid itself coil inside has short to ground or harness connector wire touching to valve body ?

explained in the link I gave you before in post 52, see under correction, rotate the solenoid valve for converter lock up clutch as shown...that there is sufficient gap between the connectors and trans housing. tighten the solenoid in the new position.
So apparently the wiring/connectors of the solenoid can touch the transmission housing.

[Annddrriy]

I don't thing this is a problem the problem cause solenoid get short inside the coil from oil. Oil like a water transffer electricity than positive connect with negative and make a short circuit nothing else we can do except to put good quality solenoids. With oscilloscope wave pattern you can see how it works connection between transmission control module and solenoid ground wire.

[Annddrriy]

Idling engine for half an hour few days than when turn ignition on all light come up on dashboard except check engine light not coming on dashboard sometimes only what is that mean I don't know ?

[shogun]

Maybe capacitors, quote: broken capacitors in the instrument cluster can be the cause of the instrument cluster acting like its haunted. http://bmwe32.masscom.net/johan/dash...dash_caps.html
also check the ground cables under the dash, plug in back of cluster X17 brown has pin 1 and 13 br/sw to ground, somewhere under dash near steering column, see ETM

[Annddrriy]

Ok thanks I'll check that. One time I was cleaning all pins under the dashboard maybe one pin did not clean up properly. Car had problem before until I clean the pins for reverse gear mirror tilt not moving down when gear selector is set to position R. Now each time selector in R position passengers mirror moves down. The wire harness for mirror control switch is on the driver side door and wire harness in passengers side door has six very small pins.

[Annddrriy]

I have two CPS sensors. Checked crank shaft position sensor resistance in one sensor ohms 536 and in another one is ohms 523 what sensor of these will work better ? Thanks !

[shogun]

Both should work fine, as they are both within the specification, 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

[Annddrriy]

If pulse sender has 0 ohm it will work ? Thanks !

[shogun]

that is all in the Bentley and workshop manual:
M30/M70 ignition system data , Bentley manual: 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.

[Annddrriy]

Cylinder identification sensor coil resistance at 20 degree C (68 F) <1 ohm, pulse sender it doesn't write how far can go minus < 1 ? Can it go to negative < -0.0 and work good ?

[shogun]

workshop manual says for cylinder identification sensor/donut nominal value at 20 degree C <1ohm between pin 1 and 2 and between pin 2 and 3 nominal value >10MOhm, there is nothing mentioned about minimum low, if that would be important, it would have been mentioned

Negative? Do you really measure that or is that just your learning and asking?
What does a negative ohm reading mean?
A negative ohmic reading indicates that the circuit you are measuring is not passive. It has some voltage on it. The cable may be connected to a powered-up circuit, or there may be a capacitor between the cable and ground that was charged up when the circuit was powered and is slowly discharging.
https://en.wikipedia.org/wiki/Negative_resistance

[Annddrriy]

I did measure that between pin 1 and pin 2 at 25 degree C 00.2 ohms at multimeter scale 200 and at scale 20k 0.00 ohm. Measured between pin 2 and 3 nothing is there at scale 20m the scale it show 1 . I ask and learn.

[shogun]

check the settings of your multimeter, maybe you measured 0.2ohm, I checked more for you, in a German language online repair manual for the E34 called "so wird's gemacht" Reparaturanleitung BMW 5er 1987 - 1995 (90-218 PS) by Dr. Rüdiger Etzold: on page 69 there are the electric data for the ignition system for the M20 and M30 engine, it mentions for resistance values:

at 23 degree C +/- 5 degree C
crankshaft position sensor 530 +/- 30ohm
cylinder identification sensor / donut 0.2 - 1ohm
temperature feeler engine
at coolant temp. of 20 +/- 3 DC 2.3 - 2.7 Kohm
at coolant temp. of 80 DC +/- 3 DC 0.3 - 0.36 Kohm

temperature feeler intake air
at temp of 20 +/- 3 DC 2.5 - 2.7Kohm
at temp of 50 +/- 3 DC 0.76 - 0.91 Kohm

ignition coil M30
primary 0.4 ohm
secondary 9.0 +/- 1 Kohm

distributor rotor 1 Kohm +300ohm - 100ohm

angled plug of ignition wire 1 Kohm +/- 200ohm
ignition boot on spark plug of ignition wire 5Kohm +/-500ohm

https://sowirdsgemacht.com/books/view/67

[Annddrriy]

I am using very cheap multimeter this tool sometimes not give me correct reading and keep changing numbers itself without connecting leads to power and ground I paid for it $20 only. I will buy better multimeter Snap-On or Blue- Point is very good product. I have one in Ukraine Snap-On. I think I need one in Canada. Thank you !
multimeter powerfirst.jpg

[shogun]

so I assume it is just a multimeter problem and the cylinder identification is in the correct range of 0.2 - 1 ohm. But most multimeters are not accurate below 1 ohm, and some cannot even measure accurately below 10 ohm. Here is an article: Rather than purchasing a special four-wire or low-resistance ohmmeter, you can reasonably measure down to 10 milliohms or less with a common multimeter in millivolts mode. http://www.robotroom.com/Measuring-Low-Resistances.html

[Annddrriy]

at coolant temp. of C 20 +/- 3 DC 2.3 - 2.7 Kohm. This test needs ignition on engine is running multimeter scale at DC volts ?

[shogun]

DC means Degree Celsius, not DC Volt. Test w/o engine running, just remove the plug from the sensor and test on the 2 pins, here all test data by different temperatures
http://www.e32-schrauber.de/bmw/date...u-2_5-kohm.png

if you want to read hot temps, taking Hot and cold readings https://www.youtube.com/watch?v=ZX3lbi9yGuE&t=141s

[Annddrriy]

My multimeter has scale resistance 20M how to find out this is miliohm megaohm or licroohm ? Thanks in advance !

[shogun]

read the user manual for your Power-Fist-8347676 multimeter https://www.manualslib.com/manual/12...?page=3#manual

[Annddrriy]

This manual doesn't write anything about 20M this is miliohms or something else. As I understood from Google search engine convert calculations 20M convert megaohm than microhm. The 20M Ohm is 000. One thousand Ohms is one million Ohms. Before we can use a multimeter to record resistance readings, we need to check the accuracy of each range against a known resistance value.

[shogun]

How to Read a Digital Ohm Meter https://www.wikihow.com/Read-a-Digital-Ohm-Meter
https://www.unitconverters.net/elect...ohm-to-ohm.htm