Spark Plugs keep fouling & P0172 code

[Jerome Nelson]

What are your short- and long-term fuel trims when this happens?

Please see above message. Thanks!

 

[Jerome Nelson]

I finally had a chance to run diagnostics on my Tahoe with my Blue Driver. I took a short, 20 minute trip with a mix of stop-and-go and 50m/hr highway.
The short and long trim was mostly in the -10% to +10% range - with the exception of a couple of +/-100% blips. I'd guess these would happen about every 4-5 minutes. (Please see images.)

I'm not going to pretend I know what I'm talking about. But, I think I heard that the +/-10% was normal/good. I'm not sure what the +/-100% blips are telling me. Any thoughts?

@strutaeng thoughts?