Ya, ignition parts need to be AC Delco. What does your misfire counter by cylinder show? What is your CMP retard? Can you feel the misfires?

George

 

Well my new icm is a standard again because that all I could get for one day shipping from Amazon. I talked to my parts supplier and he said they've never had any problems with them. I can feel the misfires bigtime. I'll check the cmp again. If i remember correctly I need to increase the rpms to check it ? 2000 rpms or something ? I'll look at the misfire on all cylinders ...I might go do that now and let ya know.

 

I check it @1600 and 2000 rpms...CMP is 2 the most I seen it was 2.2 so that shouldn't be a problem ?....misfires on #4 is crazy like 80 a couple misfires on #1 and 5. Because the misfires are so much on #4 would they have an effect on #1 and 5 ? Could the spark be jumping around in the cap because of #4 ? I replaced 1... 3 and #5 wires.I have new wires for #2 ...4 and 6 I'm gonna replace the #4 wire tomorrow and see if that fixes things and if it does I'll put the #2 and 6 wires on for a full wire replacement. I think the number 4 wire got beaten up badly from all the misfiring previously.

 

They say this company is Blue streak. I'm gonna take your advice and order the Delphi George. Im gonna replace #4 wire and if its all good replace the remaining 2 wires cross my fingers and hope for the best end result 😄

 

Your CMP retard should be good enough.

1. Check your spark plug boots, its easy to have one that did not seat correctly.
2. Double check your ignition wire routing
3. Double check your distr cap to make sure its seated correctly and the screws hold well
4. Did you mist the engine in the dark to look for arcing?

George

 

Hi George
I installed new icm today and put the remaining wires on. I noticed that I had got dielectric grease on some of the spark plug tips so I cleaned that up Oops. That's a first. No cel light.Everything is so tight on these blazers. I don't why someone designed it so that the stearing colum has to be moved aside to get #3 spark plug out. So now I have ac delco wires on Delphi coil and icm. Rotor is ac delco and a cheap Chinese cap with brass terminals. So I just ordered a Delphi cap and rotor to completely have all good parts. I have no misfires when driving now but when I'm idling I get 30-50 misfires on #1 and minor misfires on random cylinders but not all the time that's why I ordered the new cap and rotor. I guess I'll have to see Wednesday when I replace the cap and rotor if that solves the problem. If not I have a couple brandnew plugs so I'll replace the #1 plug . Maybe a bad plug. In the meantime I'll mist the wires and see if I can see anything. Driving the truck is like a dream now other then when I'm at at set of lights at idle seeing #1 going crazy. The odd time it doesn't and everything stays at zero's. I hoping the cap is the culprit. It being a cheapo cap and the rooting of the terminals in the cap. I've heard before that the cap rotor and wires need to be factory parts. Just like you said with the coil and icm. These trucks are fussy on ignition parts. Well I'll keep you posted on the outcome but I'm close to getting a %100 😄.


Thanks
Jason

 

Good luck

George

 

Thanks I need it

Jason

 

Hi George

Still waiting on parts but i have a question. Is it possible for a cam sensor to cause misfiring ? If the answer is yes what would be the easiest way to test. Is there a way by using a scan tool or do I have to take it out to test it. I see some youtube videos where they test it in the vehicle with the ignition on and prob the signal and ground and using a piece of metal near the sensor.

Thanks
Jason

 

Watch your CMP retard as a solo parameter (if using BT/android) and see if its stable or erratic.

George