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In some GM ecotec engines (z18xer), the coil packs seem to be very sensitive to spark gap. Too big of a gap or worn plugs kill the coil pack.
What makes certain spark plugs not work in certain engines?
- Thread starter Chris142
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What does that even mean? Considering there aren’t any “copper” plugs, nearly all plugs have a copper conductor in the insulator and the differences come at the tip, cheap “copper” plugs are typically nickel.
So are you saying the anti-knock system relied on using one of the cheapest plugs available?
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Ion knock sensors via spark plugs. That system is sensitive to spark plug type and gap. Here is some background to this neat technology:
https://eeuroparts.com/blog/tech-corner-saab-trionic-and-ionization-sensing/
Regardless, there are advantages to copper spark plugs in some applications. Exotic spark plugs might be better for most of us for longevity, however.
Well, that’s somewhat interesting but I still don’t see how it’s dependent upon tip material. Which again isn’t copper.
If you watched the firing lines on an oscilloscope you might see why.
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I remember on my 1998 Maxima the forum said to use OE only, so I did, didn't question it. But on my 335i, Bosch was $3/ea cheaper, so I used Bosch. Bosch makes the OE as well, so the way I saw it was one plug was blue, one was green, and I went for the $18 savings. On the Lexus I simply used Denso as Toyota OE is ridiculously expensive. Pretty sure the Denso were not OEM they were aftermarket. That was 30k ago and no issues. Bought on amazon too. When I pulled out the plugs I think they were original but the part didn't match OE. Others on the forum said the same. But the main thing was 8/8 were the same. 7/8 being the same indicates a dealer job.
How does that relate to the article that was linked?
How do YOU you see it reacting/not relating?
Funny, I wasn’t the one that said something about oscilloscope traces. I thought perhaps you understood what you were saying.
I did read the article and I just didn’t see what the connection was.
Copper-core resistor plugs. Most ran recommended NGK''s, Platinum or regular was fine.
BCPR6ES-11 or 7ES depending on tune.
Knock detection was done between sparks.
Thanks. Yeah nearly all plugs have a copper core and a resistor. That’s where I was confused.
Oh I do, I would think anyone who has watched them on different material plugs.
I just think you should do your own home work, apply the same sort of effort you use to reference 25 previous threads on a question.
Here's a little something to start with though there are many more articles like this.
https://www.hotrod.com/how-to/hppp-0612-pontiac-ignition-systems/
There is a significant difference in the wave form between say a Bosch super and a Bosch Platinum (i've actually watched those two in the same engine) in the firing line and duration. It would defiantly confuse a system that is looking for a particular voltage or resistance or spark duration.
Please use OEM spec plugs in the engine. Examples Delco for gm, motorcraft for Ford's etc. OEM plugs were selected for the engine by the manufacturer for a reason. Just because a plug crosses over doesn't mean it's the same. Heat ranges, materials the plugs are made of, all come into play on these computerized engines
Could you tell us more?- sounds very interesting
Not speaking for anyone but you can graph misfires on a data stream and see which cylinder is misfiring and when. Or you can scope each cylinder, set your time base as such so to actually see the entire firing event on a scope ( oscilloscope). This is just a very small portion of advanced diagnostics needed for today's vehicles
Thank you. I misunderstood your post- I thought you meant one could see the difference between Bosch and other brands on the scope.
Just my experience, but I have used all sp brands in about 25 cars (and 4 motorcycles) and never had a problem. Don't understand what the problem is unless its due to heat range- one plug brand maybe a better match for the spec'd heat range
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Exactly. Heat ranges, plug electrode material, . But yes essentially that's the difference
