engine misfire
Thread Starter
Burning Brakes
Joined: Apr 2011
Posts: 1,017
Likes: 229
From: Bay City Michigan
engine misfire
I am having a slight misfire on the number 4 cylinder on my 81, engine has a stumble and can feel it at idle. Replaced spark plugs with no improvement, what should i try next. New plug wires, distributor cap? Also wondering if the computer could be an issue, not sure exactly what it does for just the motor. Had the rear shocks replaced last week and the guys have a tester that he showed me when he put the thing near that plug wire it shows voltage or power then all of sudden drops to nothing then goes back to normal. Car seems to run fine at full throttle. Thanks!
Dr. Detroit
Joined: Mar 2012
Posts: 10,093
Likes: 4,017
From: New Braunfels Texas
Plugs, wires, cap and rotor......standard tune up.
The computer runs the distributor and the mixture solenoid in the carb (the blue plug sticking out of the top pass side of the carb).....this is ALL the computer does......the computer by itself cannot cause a slight miss.....if it did cause a miss it would make the carb run pig fat and black smoke out of the pipes......even bad or zero computer timing will not cause a miss, and if it did, the car would have very little or low power.
Jebby
The computer runs the distributor and the mixture solenoid in the carb (the blue plug sticking out of the top pass side of the carb).....this is ALL the computer does......the computer by itself cannot cause a slight miss.....if it did cause a miss it would make the carb run pig fat and black smoke out of the pipes......even bad or zero computer timing will not cause a miss, and if it did, the car would have very little or low power.
Jebby
Thread Starter
Burning Brakes
Joined: Apr 2011
Posts: 1,017
Likes: 229
From: Bay City Michigan
Talked to my guy today and he said he was measuring burn time on the wire. It was reading a number then all of a sudden went blank....then it came back again. Cap and rotor available from parts store or Ecklers ?
Dr. Detroit
Joined: Mar 2012
Posts: 10,093
Likes: 4,017
From: New Braunfels Texas
Jebby
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
If you are replacing the wires, just use a box cutter to slit the plug 'sockets' lengthwise. You may still have to peel them off. When you install the new wires, put some battery grease on the plug contact and the ceramic plug body so you can remove them more easily later.
P.S. change the wires one-at-a-time so that you can't make any mistakes. If you pull the old ones first, you have no 'map' to work to.
P.S. change the wires one-at-a-time so that you can't make any mistakes. If you pull the old ones first, you have no 'map' to work to.
