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Read my spark plugs - running rich, heavy fouling

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Read my spark plugs - running rich, heavy fouling

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Old 05-17-2018, 12:12 PM
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Read my spark plugs - running rich, heavy fouling

I had the same (though less pronounced) ticking noise as shown in this video.

Members of this forum suggested I change the spark plug wires, which I had my dealer perform with Racing Beat wires. (This did not solve the ticking.)

The dealer wrote in the notes (this dealer doesn't bother to explain much) that my "rotor 1 leading plug is missing tip" so I ordered a new one to replace it. When I pulled the original plug, I noticed a ton of fouling and carbon build up after just 5,000 miles.

The engine feels strong and doesn't have any issues starting. I had experience some wobble/dying at idle a few months back when my battery was constantly being discharged due to a faulty alternator, but haven't experienced it since. My gas mileage has always been **** poor (I rarely get over 15 mpg), but I attributed that to aggressive driving and just the design of the rotary engine.

Compression test from 59k miles (now at 65k) also included. Any ideas?
Attached Thumbnails Read my spark plugs - running rich, heavy fouling-20180517_005741128_ios.jpg   Read my spark plugs - running rich, heavy fouling-20180517_005803616_ios.jpg   Read my spark plugs - running rich, heavy fouling-2018-05-17-10_08_34-info%40palmspringsmotors.com_20151208_162843.pdf-adobe-acrobat-pro-dc.jpg  
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Old 05-17-2018, 12:54 PM
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My looked kinda gross after 10k miles, but not as bad as yours.

Which coils were you using?

Also, when you say you are running rich, have you looked at your LTFT and STFT?
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Old 05-17-2018, 01:00 PM
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OEM ignition coils, replaced 4/16 (under 6k miles ago).
I have not performed any tests to verify I am running rich-- just my own conclusion from the plugs.
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Old 05-17-2018, 01:15 PM
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Do you have an OBD reader and can you check your fuel trims (STFT, LTFT) on a warm idle.
90% of rich conditions are just vacuum leaks.
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Old 05-17-2018, 04:48 PM
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does the tick increase with RPM? I dont think it has much to do with spark, because even at say 1,000 rpm idle each plug would be firing at 48x per second which is way faster than that tick. Is it louder on the exhaust side or plug side?

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Old 05-17-2018, 04:51 PM
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In terms of volume, no-- the engine noise drowns it out above ~ 1500 RPM.
In terms of frequency I can't tell due to the above.

Thanks,
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Old 05-17-2018, 05:01 PM
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It sounds like an exhaust leak of sorts. I would jack the front end way up (along with the back) and probe droid around all sides of the motor and try to pinpoint where you can hear the loudest ticking noise from. Harbor freight sells a mechanics stethoscope for $4.
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Old 05-23-2018, 11:23 PM
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Here are some STFT and LTFT reads from my Torque app at 0 and 2500 RPM. Not sure if this is helpful at all.

Images are rotated but here is the readout:

Idle (804 RPM):
STFT: +3.1%
LTFT: +1.6%

@ ~2500 RPM:
STFT: 0.0%
LTFT: +1.6%
Attached Thumbnails Read my spark plugs - running rich, heavy fouling-20180518_015822808_ios.jpg   Read my spark plugs - running rich, heavy fouling-20180518_015828898_ios.jpg   Read my spark plugs - running rich, heavy fouling-20180518_015643538_ios.jpg   Read my spark plugs - running rich, heavy fouling-20180518_015649595_ios.jpg  

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Old 05-23-2018, 11:28 PM
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And here is a link to a video I took today showing the pronounced clicking.
https://1drv.ms/v/s!Avww3gBnZPRbylCYK5vXc25-lPkZ

Notice that Rotor 1 Lead Spark Plug wire "jumping".... perplexing as all hell.
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Old 05-24-2018, 07:30 AM
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Fuel trims look good
Spark plug wires are a bit of a weird thing to recommend on thrir own, but that missing electrode is probably not good for the coil attached to that spark plug. Do you have a coil you xan replace it with to test?

Also that electrode is somewhere, potentially in the engine. I'm not sure what can be done to get it out, but it could have caused internal damage.

The frequency sounds in line with spark ignition at idle. Spark plugs fire 13x a second on a 800rpm idle, which matches the sound imo.

Last edited by Loki; 05-24-2018 at 07:36 AM.
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