Wont start, barely any spark.
Thread Starter
Instructor
Joined: Jun 2010
Posts: 152
Likes: 40
From: Queens NY
Wont start, barely any spark.
I was driving on the highway when all of a sudden my ignition shuts off and the engine slowly turned to a halt. The engine turns, everything in the ignition system works or was replaced. I replaced the ignition control module, ignition coil, and checked all the contact points for resistance. Everything seems fine, im getting fuel. When I turn the key, the spark plug sparks just once (not even a strong spark) and then goes back to no spark while still turning. I've run out of ideas. Could it be the computer? Also, the motor was running hot because I had to replace the thermostat. Could the heat have caused the lack of spark?
Thread Starter
Instructor
Joined: Jun 2010
Posts: 152
Likes: 40
From: Queens NY
ooh i forgot its a late 87 so the parts are mixed 87/88. I had to buy an 88 ignition control module even though everything is stock 0_0
Im thinking it could be the spark plug knock sensor, or maybe something else wrong with the distributor that I missed?
I'm pulling my hair on this one.
Im thinking it could be the spark plug knock sensor, or maybe something else wrong with the distributor that I missed?
I'm pulling my hair on this one.
Last edited by envisi0n91; Aug 3, 2010 at 10:24 PM.
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
The spark module gets pulses from the pickup coil in the distributor. If the pickup coil is defective, no spark. You can check the pickup coil with an ohmeter. Unplug the spark module and measure the resistance across the green and white wire on the plug going to the spark module. The ECM pulses the injectors from reference pulses out of the spark module. You need to see if there are pulses on the purple/white wire out of the distributor. No pulses, possible pickup coil or spark module problem. If all ok, then look at the rotor, there is a hemispherical feature below the center of the rotor. Look for a carbon track here. While you have the distributor cap off, look inside for carbon tracks and if they are there, replace the dist cap. Measure the resistance of each spark plug wire, they should be about 5000 ohms per foot. Plug wires should be held in place by wire looms. Replace missing or broken wire looms. Plug wires should not touch any metal in their run. At night with the underhood lights off, have someone crank the engine and look for sparks along each plug wire. Replace the new spark coil with the old one and/or find a parts store that can test your new coil.
