2002 4.3l Sonoma idles rough. Put in a new dist cap, rotor & wires. Still rough idle. Changed the coil. Removed ICM and coil bracket. Replaced coil(oem). Now I get no crank, No spark..?
2002 4.3l Sonoma idles rough. So I replaced dist cap, rotor & wires. Still rough idle. Then changed the coil. Removed ICM and coil bracket. Replaced coil(oem). Now I get no crank, No spark..?
Recheck all connections and grounds to make sure they are connected and grounded properly first. If the engine idled rough but ran, put the old coil back in and see what happens. You could have bought a "new" but already bad coil.
Mark, Thanks. I did try the old coil,,,but have the same condition either way. I have tried jumping it thinking maybe my battery is weak...but that does not work either. I wonder if there is some code that needs resetting. I'm told that the started should crank even if the coil were disconnected. It seems as though my coil change is not related to my no crank condition....???
You need to change your ignition control module. It is located inside the distributer. An AC Delco one will cost you aproximately $50.00 and a generic one will cost you in the $20.00 range. Your truck will fire right up. That little module controls the signals coming and going from the trucks cpu. so 1) charge your battery so you have a good battery to work with. 2)change the ignition control module. draw a diagram where all the wires come and go off it. 3)put cap and rotor back on 4) start up the truck. once the truck is running, if it does the same thing in a couple of weeks , you may have to replace a ignition control module again. If it does it again, replace the distributer, with a brand new one, NOT a rebuilt one. rebuilt ones may have the same problem, and all they did was replace the ignition control module and send it off. It's what happened to me. Now I have an extra distributer that's a year old, that I won't turn back in.
Victor, Thanks for the response. Actually the ICM is mounted on the same bracket the coil is(not in the distributor). I will take mine in and have it bench tested, but I don't have much hope it will fix my problem. Will a bad ICM really cause a ''no crank'' problem? I can see it causing a ''no start'' but not a ''no crank''. But thanks.... Old Jim
Looking for a Used Sonoma in your area?
CarGurus has 515 nationwide Sonoma listings starting at $1,995.
Search GMC Sonoma Questions
Are you a UK consumer? CarGurus now has a discussion forum in the UK.
GMC Sonoma Experts