Misfire awful smell of sulfur?

2013 BUICK ENCLAVE
120,000 MILES • 3.6L • 6 CYL • 4WD • AUTOMATIC
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BECKAMCGINNIS62
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Started misfire 2, change coil, then it had a awful smell of sulfur, then new coil had melted spots and fuses blown, starts, no overheating, no knocking, no leaks. Only sluggish, like no power, trying to figure out what it is?
Jun 2, 2025 at 5:27 PM
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STRAILER
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Do you have any trouble codes? We should run the computer to see if any are stored even if you don't have a check engine light on. I have seen the fuel pressure rail sensor go out and over pressurize the system which makes it run rich. Also, a bad fuel injector can do this as well, but you should have a misfire on the cylinder that is having the issue.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

The short trim fuel trim should be way in the negative number as the system tries to lean the mixture down. Here is the location of the pressure sensor in case a code is present for it, or you just want to try to swap it out. Check out the images (below). Please upload pictures or videos in your response.
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Jun 3, 2025 at 11:22 AM