Hi All,

I've searched a bit on here but can't quite figure out what the problem is with my 2001 Blazer. It was running fine and then all the sudden.... crank but no start. I have diagnosed that there is power up to the coil... but no spark out of the coil to the distributor. I have put the ohms meter on the coil and I'm getting 6.78K on all three prongs to the main post. I have actually put another used coil that I have from a 1999 blazer just to make sure. Same issue. I have also tested the output post side of the coil with a spark tester and nothing. I have added a couple of photos for reference. The plug going into the coil has a pink wire and a white/black wire. Pink has power with key on when unplugged and stays hot while cranking. White/black does not. Both pink and white/black have power when plugged into coil with key on and while cranking.

I have replaced the Ignition control module. The plug to the ICM has 4 wires. Pink, White, Black/white, and White/black. Pink and the White/black are hot with key on and stay hot while cranking. On a side note... I also have power to the cam shaft sensor.

I'm at a loss. Not sure why I'm not getting electrical output from the coil? Any ideas? I'm happy to provide other info as I'm sure someone here has the answer.

Thanks for any help you all can provide! I really appreciate it!

Corey

 

***Update***

So after some additional troubleshooting I saw a video on how to run power to the signal (white) wire on the ignition control module in order to generate spark in the coil (basically bypassing the ECM). It worked! I put my spark tester on the output of the coil and ran the test. Got spark! So that ultimately told me my coil was good and narrowed it down to three things.... cam position sensor, crankshaft sensor, or ECM. I bought a new crankshaft sensor and a cam position sensor and thought I'd just replace both. I went ahead and did the crankshaft sensor first.... and bang! It started up. Thank goodness! Guess I'll return the camshaft position sensor tomorrow. Hope this can help someone else.

 

Congrats!!

Nice job on the troubleshooting.

And thanks for the update.