resistor plugs, what may happen if you don't use
- steptoe
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resistor plugs, what may happen if you don't use
Pinched from the NGK website FAQ's. Thought I might remember detail better if it stays in here
Frequently Asked Questions
Q: When should I use a resistor spark plug?
A: NGK "R" or resistor spark plugs use a 5k ohm ceramic resistor in the spark plug to suppress ignition noise generated during sparking.
NGK strongly recommends using resistor spark plugs in any vehicle that uses on-board computer systems to monitor or control engine performance. This is because resistor spark plugs reduce electromagnetic interference with on-board electronics.
They are also recommended on any vehicle that has other on-board electronic systems such as engine-management computers, two-way radios, GPS systems, depth finders or whenever recommended by the manufacturer.
In fact, using a non-resistor plug in certain applications can actually cause the engine to suffer undesirable side effects such as an erratic idle, high-rpm misfire, engine run-on, power drop off at certain rpm levels and abnormal combustion.
and Aaron, if you are reading this from your cell at AMC, this may be what was wrong with your EJ20G'd Brumby !
Frequently Asked Questions
Q: When should I use a resistor spark plug?
A: NGK "R" or resistor spark plugs use a 5k ohm ceramic resistor in the spark plug to suppress ignition noise generated during sparking.
NGK strongly recommends using resistor spark plugs in any vehicle that uses on-board computer systems to monitor or control engine performance. This is because resistor spark plugs reduce electromagnetic interference with on-board electronics.
They are also recommended on any vehicle that has other on-board electronic systems such as engine-management computers, two-way radios, GPS systems, depth finders or whenever recommended by the manufacturer.
In fact, using a non-resistor plug in certain applications can actually cause the engine to suffer undesirable side effects such as an erratic idle, high-rpm misfire, engine run-on, power drop off at certain rpm levels and abnormal combustion.
and Aaron, if you are reading this from your cell at AMC, this may be what was wrong with your EJ20G'd Brumby !
- steptoe
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Funny, leads appear to be going through a change and offering lower resistance levels than before. I use and recommend the Eagle Products Eliminator series, 8.0mm black with sexy gold print. Plug ends are well made with a finger grip for removal, made west of Sydney (047) std code area, the box smells nice too
The box claims it is a perfect partner with NGK!

- mud_king91
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- mud_king91
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- Gannon
- Senior Member
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Low tension leads? 
Aren't they high tension?

Aren't they high tension?
Current rides: 2016 Mitsubishi Triton GLS & 2004 Forester X
Ongoing Project/Toy: 1987 RX Turbo EA82T, Speeduino ECU, Coil-pack ignition, 440cc Injectors, KONI adjustale front struts, Hybrid L Series/ Liberty AWD 5sp
Past rides: 92 L series turbo converted wagon, 83 Leone GL Sedan, 2004 Liberty GT Sedan & 2001 Outback
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Ongoing Project/Toy: 1987 RX Turbo EA82T, Speeduino ECU, Coil-pack ignition, 440cc Injectors, KONI adjustale front struts, Hybrid L Series/ Liberty AWD 5sp
Past rides: 92 L series turbo converted wagon, 83 Leone GL Sedan, 2004 Liberty GT Sedan & 2001 Outback
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- littlewhiteute
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- mud_king91
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- steptoe
- Master Member
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- Joined: Thu Oct 06, 2005 10:00 am
- Location: 14 miles outside Gotham City
I had a diagnostic ride in a standard looking Brumby - apart from the 3" tail pipe.
Oh, and under the bonnet was a a little non standard....

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The indash ECU readout from the MTX8 was indicating the temps and fuel trims etc and just within a few degrees of optimal operating temp the 16psi boosted EJ20G had weird power issues. It only took a few degrees either side of optimal op temp not to do it. Owner squirmed a little at the thought of new coils as he had already fitted used. I think engine had to be lifted off mounts to access plugs.

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I never got to learn of any resolution - owner got locked up.
The explain above reads just like its symptoms
Oh, and under the bonnet was a a little non standard....

Uploaded with ImageShack.us
The indash ECU readout from the MTX8 was indicating the temps and fuel trims etc and just within a few degrees of optimal operating temp the 16psi boosted EJ20G had weird power issues. It only took a few degrees either side of optimal op temp not to do it. Owner squirmed a little at the thought of new coils as he had already fitted used. I think engine had to be lifted off mounts to access plugs.

Uploaded with ImageShack.us
I never got to learn of any resolution - owner got locked up.
The explain above reads just like its symptoms
- steptoe
- Master Member
- Posts: 11582
- Joined: Thu Oct 06, 2005 10:00 am
- Location: 14 miles outside Gotham City
OK . Now that I have fitted resistor plugs BCPR6ES-11 in my EA82TS I find this in the Australian Supplement of the handbook

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Next time I will be buying BCP6ES-11

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Next time I will be buying BCP6ES-11
- Gannon
- Senior Member
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- Joined: Sat Nov 05, 2005 10:00 am
- Location: Bowraville, Mid Nth Coast, NSW
Yeah early EJ20G coils are well known for being troublesome. Most opt for a remote bosch coil and lead setup.
Current rides: 2016 Mitsubishi Triton GLS & 2004 Forester X
Ongoing Project/Toy: 1987 RX Turbo EA82T, Speeduino ECU, Coil-pack ignition, 440cc Injectors, KONI adjustale front struts, Hybrid L Series/ Liberty AWD 5sp
Past rides: 92 L series turbo converted wagon, 83 Leone GL Sedan, 2004 Liberty GT Sedan & 2001 Outback
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Ongoing Project/Toy: 1987 RX Turbo EA82T, Speeduino ECU, Coil-pack ignition, 440cc Injectors, KONI adjustale front struts, Hybrid L Series/ Liberty AWD 5sp
Past rides: 92 L series turbo converted wagon, 83 Leone GL Sedan, 2004 Liberty GT Sedan & 2001 Outback
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Funny things spark plugs, my old man bought an MY97 forester brand new after first service ran terrible, took it back to the dealer, asked what they did, they said nothing but oil & plugs, etc. He then read the manual and from memory it said something like 'use ONLY champion plugs', he changed the dealer fitted NGK's to champs and ran like a charm again! Funny aye, and obviously only some EJ20's as Ive had some plugs that were branded both 'NGK' and 'STI'
The trading corner : the stuff that I need ATM -
# Vortex Main Dash Surround / Bezel ANY COLOUR,
# Vortex Radio, # RHD Vortex 4speed auto digital dash,
# RH-Side parking (86+) Vortex wiper transmission,
# EA82 AWD 4EAT,
If you have them please PM me
# Vortex Main Dash Surround / Bezel ANY COLOUR,
# Vortex Radio, # RHD Vortex 4speed auto digital dash,
# RH-Side parking (86+) Vortex wiper transmission,
# EA82 AWD 4EAT,
If you have them please PM me

- mud_king91
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