Need help diagnosing my non starting E30

[zippy320]

Hi Guys!

as some of you may know or have been following my woes (it has been a little educational I guess) , I have been busy , kind of restoring /waking up my 88 E30 320i Automatic .

As per this thread

http://www.bmwfanatics.co.za/showthread.php?tid=67168

Car had been sitting for over 10 years , Much has been done to it in this past few months though , replacing many pieces .

I had managed to start it , found that the Alternator regulator wasn't charging , replaced the voltage regulator , tried starting it and it started showing that it was now indeed charging , closed everything up , and then it wouldn't start , opened everything up again , checked the ECu relay , replaced it , and it started , Now closed everything up from under the drivers side , and it wouldn't start again.

I tested the wiring loom to the ECU and these are the results below . (THE ecu was disconnected ) I just probed those pins .

I don't now how to test Continuity ..... I have a normal ohmmeter , how do I test it? Where do I point the needle? If I put a probe on 2 14 19 24 . where do I put the other probe?

Also im not getting any reading by touching pins 5 and ground , non at all , what is Evaporative emissions purge valve?

My car has a motronic 1.3 ECU so , it is possible to read codes from it though I dont have the correct cables

Someone help ..

 

[KENNY432]

Hi

With the ecu unplugged pins 2, 14, 19 and 24 must give you continuity to earth.
So multi meter on Ohms - black lead on earth red lead to pin 2.
You should get continuity.
Continuity meaning no break in wire.
If you touch the black and red lead together on Ohms setting most Multi-meters will go close to 0.00 depending on your settings.
So any wire will have a little resistance.
So if you are measuring continuity it wont be 0 it will have some resistance.
If there is a break in the wire (open circuit) you will get the same reading as if you held the 2 probes apart not touching anything.
The above mentioned wires must all be earth.

Pin 52 and 53
first place red lead in pin 52 and black lead on earth.
You should get continuity to earth.
When you press accelerator pedal the continuity should change to open circuit.
So the earth is only there when accelerator is not pressed.

On pin 53 you will only get continuity to earth if the accelerator is pressed fully open

 

[zippy320]

Thank you so much Kenny! This really really helped ! I was clueless as to where to start with that piece of the puzzle . I really appreciate it!

I tested all and everything turned out fine . 0.00 on all pins 2 , 14 , 19 , 24

Tested Pins 52 , When the pedal is left alone (throttle closed) I get 0.00 , If I press the acc down , that 0.00 changes , not giving me a reading but looks like error or something , I assume that's not continuity.

Pin 52 , when I press the pedal all the way to the floor it gives me a 0.00 .

So all of that is fine .

Alll pins are giving me correct readings and everything seems fine . The readings are all spot on exactly as per that data sheet.

I decided to plug the harness back onto the ECU and try and start it , One turn and it started! But I don't trust it , there has to be something wrong , I know if I touch something , or close up the cover , the cars going to give me starting issues again . :blueCry:

I now know why both BMW dealerships couldn't figure out why I complained about the car not starting. Every-time I had it towed to them , by the time it arrived at the dealership while still on the flatbed truck, It started . This is bringing back lots of memories!

Sigh , I hope the car stays as it is now , but I don't have confidence in it . Just that gut feeling that Its not going to start again .

Every time I work on the car it reminds me of the Movie Christine! Hasn't killed anyone yet , Will probably kill me , its plotting its next move and toying with me . Like a stalker after its prey . Dammit

Hi

With the ecu unplugged pins 2, 14, 19 and 24 must give you continuity to earth.
So multi meter on Ohms - black lead on earth red lead to pin 2.
You should get continuity.
Continuity meaning no break in wire.
If you touch the black and red lead together on Ohms setting most Multi-meters will go close to 0.00 depending on your settings.
So any wire will have a little resistance.
So if you are measuring continuity it wont be 0 it will have some resistance.
If there is a break in the wire (open circuit) you will get the same reading as if you held the 2 probes apart not touching anything.
The above mentioned wires must all be earth.

Pin 52 and 53
first place red lead in pin 52 and black lead on earth.
You should get continuity to earth.
When you press accelerator pedal the continuity should change to open circuit.
So the earth is only there when accelerator is not pressed.

On pin 53 you will only get continuity to earth if the accelerator is pressed fully open

---

Thank you so much Kenny! This really really helped ! I was clueless as to where to start with that piece of the puzzle . I really appreciate it!

I tested all and everything turned out fine . 0.00 on all pins 2 , 14 , 19 , 24

Tested Pins 52 , When the pedal is left alone (throttle closed) I get 0.00 , If I press the acc down , that 0.00 changes , not giving me a reading but looks like error or something , I assume that's not continuity.

Pin 52 , when I press the pedal all the way to the floor it gives me a 0.00 .

So all of that is fine .

Alll pins are giving me correct readings and everything seems fine . The readings are all spot on exactly as per that data sheet.

I decided to plug the harness back onto the ECU and try and start it , One turn and it started! But I don't trust it , there has to be something wrong , I know if I touch something , or close up the cover , the cars going to give me starting issues again . :blueCry:

I now know why both BMW dealerships couldn't figure out why I complained about the car not starting. Every-time I had it towed to them , by the time it arrived at the dealership while still on the flatbed truck, It started . This is bringing back lots of memories!

Sigh , I hope the car stays as it is now , but I don't have confidence in it . Just that gut feeling that Its not going to start again .

Every time I work on the car it reminds me of the Movie Christine! Hasn't killed anyone yet , Will probably kill me , its plotting its next move and toying with me . Like a stalker after its prey . Dammit

Hi

With the ecu unplugged pins 2, 14, 19 and 24 must give you continuity to earth.
So multi meter on Ohms - black lead on earth red lead to pin 2.
You should get continuity.
Continuity meaning no break in wire.
If you touch the black and red lead together on Ohms setting most Multi-meters will go close to 0.00 depending on your settings.
So any wire will have a little resistance.
So if you are measuring continuity it wont be 0 it will have some resistance.
If there is a break in the wire (open circuit) you will get the same reading as if you held the 2 probes apart not touching anything.
The above mentioned wires must all be earth.

Pin 52 and 53
first place red lead in pin 52 and black lead on earth.
You should get continuity to earth.
When you press accelerator pedal the continuity should change to open circuit.
So the earth is only there when accelerator is not pressed.

On pin 53 you will only get continuity to earth if the accelerator is pressed fully open