Hello everybody,
Its my first post here, so take it slow with me...
Also please excuse any grammar or syntax mistakes (google takes care of spelling), English is not my mother language... so...
Now, to explain my problem, and I hope some of you Micra semigods will find the time and "bless" me with an idea or two...
The car is a 1992 1.2 K10 with cat. converter (so it has the "electronic" carb, ECU and no vacuum advance)
So the situation is this, I drive home from work, park, two hours later go back, car wouldn't start!
So, I get my Haynes manual and I try and pinpoint the problem.
First of all, petrol (gas? benzine?) goes to the engine, so fuel pump is OK (also recently replaced).
Then to check for a spark, I unplug the HT lead from the center of the distributor no spark there while I crank.
I then remove and measure the ignition coil, and its within specs, so no problems there.
Next is the transistor. Now, as an electronics engineer, i know how to test a transistor, but I dont really know
if inside the heatsink is an actual transistor, or they are just calling it that (if it is, it test out faulty)
But the transistor is getting power and ground, so if its working and it gets a trigger-pulse it should work.
Anyway, moving on.
I now want to know if the ECU is triggering the "transistor" that, in turn, triggers the coil to fire the spark.
(excuse my highly non-technical terms)
So I take out my oscilloscope (after a rig it with a battery to make it portable) and trace the wire from the
"transistor" to the corresponding ECU pin, and try to see if any kind of pulse exists there.
And... no pulse there!!! So assuming the 'transistor' is OK then thats the reason for having no spark.
But here lies the true question...
Why is the ECU not outputting an ignition pulse?
Could it be...
1) faulty ECU? (are they really capable of craping out like that?)
2) a faulty sensor (a crank position sensor, or water temp maybe?)
3) other...
I know second-hand parts are cheap but a really don't feel like throwing money at it blindly...
Any input and idea is very welcome!!!
Thank you!!!
And I am sorry for the lengthy post...
Bill...
Its my first post here, so take it slow with me...
Also please excuse any grammar or syntax mistakes (google takes care of spelling), English is not my mother language... so...
Now, to explain my problem, and I hope some of you Micra semigods will find the time and "bless" me with an idea or two...
The car is a 1992 1.2 K10 with cat. converter (so it has the "electronic" carb, ECU and no vacuum advance)
So the situation is this, I drive home from work, park, two hours later go back, car wouldn't start!
So, I get my Haynes manual and I try and pinpoint the problem.
First of all, petrol (gas? benzine?) goes to the engine, so fuel pump is OK (also recently replaced).
Then to check for a spark, I unplug the HT lead from the center of the distributor no spark there while I crank.
I then remove and measure the ignition coil, and its within specs, so no problems there.
Next is the transistor. Now, as an electronics engineer, i know how to test a transistor, but I dont really know
if inside the heatsink is an actual transistor, or they are just calling it that (if it is, it test out faulty)
But the transistor is getting power and ground, so if its working and it gets a trigger-pulse it should work.
Anyway, moving on.
I now want to know if the ECU is triggering the "transistor" that, in turn, triggers the coil to fire the spark.
(excuse my highly non-technical terms)
So I take out my oscilloscope (after a rig it with a battery to make it portable) and trace the wire from the
"transistor" to the corresponding ECU pin, and try to see if any kind of pulse exists there.
And... no pulse there!!! So assuming the 'transistor' is OK then thats the reason for having no spark.
But here lies the true question...
Why is the ECU not outputting an ignition pulse?
Could it be...
1) faulty ECU? (are they really capable of craping out like that?)
2) a faulty sensor (a crank position sensor, or water temp maybe?)
3) other...
I know second-hand parts are cheap but a really don't feel like throwing money at it blindly...
Any input and idea is very welcome!!!
Thank you!!!
And I am sorry for the lengthy post...
Bill...
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