Air Fuel Too Rich

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Does the carbon deposits on these plugs show that the engine is running too rich? These plugs, 6-1 in order, have 20k miles on them. I thought they looked decent considering the miles. A couple weeks back when I was picking up auto parts at the dealer, someone commented that the truck smelled like it was running too rich.
When the engine is cold and the idle is high it seems to emit excessive Co2. Sometimes, when I start it in the driveway, the Co2 sensor inside the front of my house will be triggered. Please let me know what you think.
Some of those plugs were loose as well so I think that accounts for the carbon on the threads of the plugs.

6A9F3519-DCA0-4B3F-8A9B-6238ECCB3EF6.jpeg
 
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Those plugs look good, from what is visible. It's the electrode and ceramic insulator you want to look at.

You're driving a vehicle with an engine that was primarily designed for extreme reliability, emissions was low on the priority list.
 
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Another thought on loose plugs - you can tell by the ignition wire boots whether there's been any blow-by. The factory boots are red, and will be blackened if there's any compression leaking out past the loose spark plugs. It's pretty obvious.
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Those 3 plug wires you see in the middle, the spark plugs were loose enough to the head that one of them spun out with fingertips on a socket extension, alone. Thats pretty loose, and was after my overheat event, which likely stretched the threads. Incidentally, that #4 cylinder is the same one that ended up having piston slap...
 
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Those plugs look good, from what is visible. It's the electrode and ceramic insulator you want to look at.

You're driving a vehicle with an engine that was primarily designed for extreme reliability, emissions was low on the priority list.
That makes sense, but does yours have that level of emissions when cold?
Warm it’s fine, and passed Ca stringent emissions standards last year.
Thank you for responding.
Dan
 
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Another thought on loose plugs - you can tell by the ignition wire boots whether there's been any blow-by. The factory boots are red, and will be blackened if there's any compression leaking out past the loose spark plugs. It's pretty obvious. View attachment 3037354

Those 3 plug wires you see in the middle, the spark plugs were loose enough to the head that one of them spun out with fingertips on a socket extension, alone. Thats pretty loose, and was after my overheat event, which likely stretched the threads. Incidentally, that #4 cylinder is the same one that ended up having piston slap...
The wires looked fine. I guess I didn’t do a good job tightening them last time.
Did tour loose plug contribute to the overheating? I guess tour plugs could have been arching with the wiring.
 
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Nope, driving a long grade at 5mph in 117F temps after letting the engine heat soak before I started, combined with me being an idiot and pushing the go-pedal the whole way, even after more than sufficient warning is what caused my short-block replacement.

I don't recommend it.

Your plugs look fine. That head gasket, though,... (*kidding)
 
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Nope, driving a long grade at 5mph in 117F temps after letting the engine heat soak before I started, combined with me being an idiot and pushing the go-pedal the whole way, even after more than sufficient warning is what caused my short-block replacement.

I don't recommend it.

Your plugs look fine. That head gasket, though,... (*kidding)

My dad lives right at the Colorado River outside of Bullhead City Az, and he keeps asking me to drive my truck out there.-- It gets like 120 there.
My engine has 60k on a complete rebuild by Toyota of Seattle. It runs like a sewing machine -- which is why I don't understand the nuclear emissions from the pipe.
 
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Keep in mind that emissions testing is done on a warm engine. Cold engines will have higher emissions, but you're going entirely off of a "smoke detector" type thing and the eye-watering quotient, not on any standard.

I'll bet the emissions are fine, those plugs look fine at 20k miles, and you're overthinking this. I've been guilty of the same, especially since my rebuild.
 
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So some random parking lot guy told you your car was running rich? What mileage are you getting? Any fault codes? I'd look for a few more indicators of issues besides some dingbat in a parking lot.
 

Comet

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First post. I read nothing after that. No. Run it like you stole it. Arm chair quarterbacks are dingbats. Those plugs look brand new.
 
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For what it’s worth, mine sets off the CO alarm in the garage from a cold start too if I don’t back it out immediately. Runs fine otherwise. Just rebuilt the top end last month. Those plugs look just fine to me. You can’t compare mid 90s start up emissions to modern vehicles.
 
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For what it’s worth, mine sets off the CO alarm in the garage from a cold start too if I don’t back it out immediately. Runs fine otherwise. Just rebuilt the top end last month. Those plugs look just fine to me. You can’t compare mid 90s start up emissions to modern vehicles.
Good to j o ring
First post. I read nothing after that. No. Run it like you stole it. Arm chair quarterbacks are dingbats. Those plugs look brand new.
Thanks. Plugs have 20k on them give or take. I wouldn't have changed them but I thought the engine was running rich. When it's cold, it is a stink bucket.- so embarrassing.
 

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