1986 Honda Civic fouling plug

1986 HONDA CIVIC
345,000 MILES • 4 CYL • FWD • MANUAL
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TRAPPEDBKD
  • MEMBER
  • 1 POST
for the past few months my car has been running poor. finally i decided to take it to a shop. compression was good but #1 cylinder was not firing. so we changed plugs. but it keeps fouling plugs. i decided to check for a trouble code. but no light code has come up on cpu. im guessing map or 02 sensor. but not sure any ideas?
Jun 12, 2008 at 11:27 AM
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MHPAUTOS
  • ✓Experienced Mechanic
  • 31,937 POSTS
Hi there,

I would be checking the ignition system on an oscilloscope as this will give you a good overall view of the ignition voltages and firing lines. Have an exhaust analysis done as well if the O2 sensor is faulty it will cause the ECU to dial up a rich mixture, but not normally enough to cause this sort of a problem. start here,

Mark (mhpautos)
Jun 12, 2008 at 11:30 AM
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