Diagnose Bad Plug Wire

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  #1  
Old 07-17-19, 12:07 PM
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Diagnose Bad Plug Wire

2000 Olds Bravada

It has a bad ticking in the radio, especially a weaker station and X-BIL says it is a plug wire. After taking the wheel off the passenger side wasn't bad, changed those wires.

Driver's side will be a bear with the steering column in the way and the horrible places they put the wire holders i.e. against the firewall and behind the brake booster.

So - could I remove one wire at a time from the distributor to see if the clicking stops?

Never tried it but I think I would have to block the empty space in the distributor? If so, what - big gob of electrical tape, piece of doweling?

She does say it runs kind of rough and sucks gas like crazy.

Thanks
 
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  #2  
Old 07-17-19, 02:07 PM
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Pull the wires out of the distributor and slide the boots up the wire a little. Then sit the wires down in the cap. Start it and pull the wires out one at a time with insulated pliers.

The ticking should stop along the way and all the wires but the bad one will affect the running when it's pulled.
 
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Old 07-18-19, 06:18 AM
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If they're original wires, just replace them. Less trouble than troubleshooting them one at a time. And even if the noise is not plug wire associated, it's good PM to do anyway.
 
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Old 07-20-19, 07:11 AM
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Simple test. In the dark, start engine.
Have soapy water mix ready in the spray can.
With engine running, spray soapy water onto spark plug wires. If you see - in the dark! - lightnings creeping from wire insulation down onto engine block, you have bad wires.
And BTW. I'd be real careful pulling running engine wires. If you never were shocked by high voltage discharge - that's about the way to try it. I was. So get insulated gloves, if you want to play with that.
You have distributor? I'd rather blame it on distributor and cap, than on wires.
You can always add suppressor to stereo... Those are commercially available;e.
Is it V6 or 4 cyl? Weird that you have to remove wheels to get to wires...
 
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Old 07-20-19, 08:42 AM
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you could also check wires with a ohm meter but since there is varying resistance values do to different suppression core materials would suspect any wire with less than 10k per foot is likely good since the core usually completely burns when they do go bad leaving a gap for the coil to overcome the resistance is usually either open or in the mohms range of a bad wire.
 
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Old 07-20-19, 09:18 AM
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It has a bad ticking in the radio, especially a weaker station
Can we assume that's AM radio...... not FM ?

Changing the cap and rotor may help.
Changing the plug wires may help.

Adding a braided ground wire from firewall to the hood is recommended.
Make sure base of antenna is well connected to ground. If questionable.... change the antenna.
 
  #7  
Old 07-26-19, 11:43 AM
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V-6 with odd distributor, 3 wires out one side and 3 on the other side.

She listens to FM, barely hear it with music, more on talk with dead air. On AM it would drive me crazier than I am.


With the wires going out the side I disconnected one wire, started it up - clicking on remaining 3 wires. I never thought it was the wires but she wanted me to check.

Hooked up my code reader and always the same two codes - P0440 & P0442 which means slow leak in gas cap or emission hose some where, doubt that causes any clicking. After erasing those codes the light might stay off a week or a month and come back.

If it was a wire wouldn't a misfire code come up?

I thought I could unscrew the antenna and put the one from my truck on, super tight so I didn't want to break something.

I'll ask at CarQuest about a ground strap and the suppressor thingie, never know.


If they're original wires, just replace them.
If I was two feet taller and my right arm was 3 feet longer it'd be a snap.


Thanks guys !!!


Oh - about sucking gas. That little thing is only rated 13-20 mpg. Can't believe it is only a hair better than my 89 K1500. I won't even go into the SmartTrac making her back end 'hop' turning on dry pavement.

 
  #8  
Old 07-31-19, 06:34 AM
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Couple days ago I sprayed the wires and cap a few times, no sparking at all.

Ordered a Ai AS100 Antenna Noise Filter, be here Friday then I'll try that if I can even find the radio. I'll have to check the book again but I think it has a Bose amp in there someplace.

Like Pete said, this kind of noise (only radio noise that increases with rpm) it is almost always the antenna and/or grounds.

I'll keep looking.
 
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Old 08-01-19, 04:37 PM
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Spraying only shows bad insulation in wire. But that is the correct test for static interference at the radio. Just get a suppressor. Alternators are notorious about creating such noise.
 
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Old 08-02-19, 08:43 AM
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Alternators are notorious about creating such noise.

During my googling one guy mentioned a diode going bad in the alternator could do that. I'd like to take the wires off the alternator but not sure if that could do some electrical damage when starting it for a few seconds?

Or maybe just take the belt off and run it for a minute? I could have the radio tuned to an AM station, I'd know instantly.

Thanks
 
  #11  
Old 08-03-19, 07:35 AM
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Took the belt off, still clicking. Filter will be here today and if that doesn't do it I'll get a new antenna.

 
  #12  
Old 08-04-19, 06:39 PM
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Does it tick on AM or FM ?
 
  #13  
Old 08-05-19, 05:41 AM
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Both, AM is really bad. Found out yesterday the filter I bought takes regular plugs, this thing has some sort of mini connectors.

Her brother bought this new then gave it to her with 145k miles on it, very nice shape except for these little things driving her crazy.

If it wasn't in such nice shape I'd start it on fire.
 
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