Hello Forum,
during driving my engine suddenly stoped working.
I got the Blazer back home and cheked the distributor (was realy worn), bought new Cap and Rotor, checked again, still no spark.
Checked direct from ignition coil, no sparc
cheked fuses: all good
cheked voltage at the red wire on the coil when ignition switch in on Position= 11,5V
cheked voltage at the wire from the coil to + terminal from ignition module when ignition switch in on Position= 11V
cheked voltage at the wire from the coil to C terminal from ignition module when ignition switch in on Position= 11V
cheked pic up coil to ground: infinite resistance
cheked pic up coil circut: steady value 850 Ohms
cheked ignition coil resistance to specifications: seems OK
bought a new ignition modul (Not GM or ac delco): no spark

Tell me please, what should I do next?
how can I test the engine controle modul?
how can I test the ignition module?
for what is the 4th (grey) wire on the igniton coil

BLAZER S10 / 1994 / 4x4 / TBI / auto / engine code Z
thank you!

 

Sure sounds like you are on the right track. Without looking the system over in my references (don't have them at work with me sorry), it sounds like you have the proper voltages at the proper places. If that is in fact true, then the next step would logically be the ECU. If you lived in the US, I would tell you to run on down to the local junk yard and grab one to try. I don't think that would be an option for you over in Germany... And most parts stores here in the states would not let you "try" an electronic component out...

 

What does your truck do when you have the key in the on position?? Does everything turn on like its supposed to?? Does it just crank and crank???

 

Is the ECU = ECM? The box under the dashboard on the right side?
I can get a used one not far from my home but it is from a 1992 S10 will this part fit to my car?
You are right, it is not easy here in germany to get spare parts for a chevrolet.

When i have the key in on position everything turns on like its supposed to.
and when I start it just crank and crank but without a spark (not even one tiny little spark)

 

Is the ECM also from a TBI vehicle? If so, it should work fine.

 

I will call this guy tomorrow and ask him.
Do you think i should change the ignition coil or the pick up coil first bevore I buy a new ECM?

 

Yes replace the ICM as that would be the easiest part to swap. Give that a shot first.

 

ICM = ignition coil module?

Do I have to take out the distributor to change the pick up coil?

 

1. Yes
2. I believe so, that's why I would change the ICM first

My truck lost spark and when reading through the haynes manual had it down to either the ICM or pickup. I just ended up replacing the entire distributor since it wasn't too expensive.

 

I will order a new ICM and try out, will need some time until it arrives.
Thank you,