How do I check for a bad plug or wire?
Thread Starter
Pro
Joined: Oct 2001
Posts: 554
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From: CA
How do I check for a bad plug or wire?
Did plugs, wires, cap and rotor. Pretty straight forward. I think the #2 plug (most forward, passenger side?) may not be correctly torqued (20#s)but it's in there securely. All the plug wire are seated securely as well. I think I'm having trouble with one plug or wire. On acceleration during city driving, i'm not getting that normal SOTP feeling all the time and it appears my avegare MPG has dropped during the city driving. During my highway driving the MPG appears normal but i'm still not getting that SOTP feeling when I go WOT...at least not all the time. I remember a couple years ago my mileage dropped significantly and I had very noticeable acceleration issues. The dealer said I had a one bad wire and i think they may have replaced the coil too. How do you test for a bad wire or plug? Plugs are Bosch platinums. Wire are Accel 8mm super stock and the cap/rotor is Accel too.
Thread Starter
Pro
Joined: Oct 2001
Posts: 554
Likes: 1
From: CA
Originally Posted by aklim
If you have an inductive timing light with a tach you can run it from cylinder wire to wire. If there is a drop in that wire, that might be your bad part
Team Owner
Joined: Dec 2000
Posts: 90,675
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From: SE NY
Cruise-In II Veteran
I found two bad dist cap plugs by clipping a timing light onto each wire and noticing when missed flashes coincided with engine miss.
You can get a simple inductive pickup timing light at Sears or an auto parts store for a few $$. The ones with a dial to set timing delay will be more expensive but not necessary for simple base timing checks and many ignition diagnostics.
Thread Starter
Pro
Joined: Oct 2001
Posts: 554
Likes: 1
From: CA
Originally Posted by 65Z01
I found two bad dist cap plugs by clipping a timing light onto each wire and noticing when missed flashes coincided with engine miss.
You can get a simple inductive pickup timing light at Sears or an auto parts store for a few $$. The ones with a dial to set timing delay will be more expensive but not necessary for simple base timing checks and many ignition diagnostics.
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