So - I have a 2008 Yukon XL Denali with 129K miles - it's a nice rig and has treated our family well as a Rocky Mountain area Hockey Team Hauler and Travel Trailer Puller - recently - I had the low oil pressure issue and my mechanic replaced the oil sending unit (which was about 1000 bucks becasue they had to take out the intake and put it back in) During that service I had them replace all belts and they did some other maintance items. Oil Pressure issue wasn't resolved and they believed the oil pump was wonky - so they replaced that and confirmed so scarring (with discounted shop rate for labor because of the runaround but assured me that the sending unit had in fact failed)
Meanwhile - the check engine light was on and I asked them to look into it (P1153 code 02 sensor) My mechanic stated that he believed it was a CAT issue and not just the O2 Sensor and sent me to a local muffler place that he said would be a better option for price and timeline for this job. Brought to local muffler joint - they confirmed both CAT's were toast - 2500 bucks for all sensors and all new CAT installed - drove for 40 miles - engine light - (P1153) - brought to muffler dudes and they were a little perplexed but ran diag and it showed the O2 sensors firing in normal range. He cleared the code - told me to drive it more and bring it right back if it kicks a code again.
Sure enough 40 miles later - Engine light - (P1153) - I bring it back to muffler dudes. They called me a couple hours later stating that the computer needs and update and it's about 250 bucks becuase it's reading emmission outputs differently in the new update which is kicking this code.
I have googled/lurked/asked around and people have confirmed this could be the issue - but wanted the opinion of this group of folks who have come across all sorts of phantom issues with these rigs. I'm about 4500 bucks into chasing a few issues! Thanks!
Meanwhile - the check engine light was on and I asked them to look into it (P1153 code 02 sensor) My mechanic stated that he believed it was a CAT issue and not just the O2 Sensor and sent me to a local muffler place that he said would be a better option for price and timeline for this job. Brought to local muffler joint - they confirmed both CAT's were toast - 2500 bucks for all sensors and all new CAT installed - drove for 40 miles - engine light - (P1153) - brought to muffler dudes and they were a little perplexed but ran diag and it showed the O2 sensors firing in normal range. He cleared the code - told me to drive it more and bring it right back if it kicks a code again.
Sure enough 40 miles later - Engine light - (P1153) - I bring it back to muffler dudes. They called me a couple hours later stating that the computer needs and update and it's about 250 bucks becuase it's reading emmission outputs differently in the new update which is kicking this code.
I have googled/lurked/asked around and people have confirmed this could be the issue - but wanted the opinion of this group of folks who have come across all sorts of phantom issues with these rigs. I'm about 4500 bucks into chasing a few issues! Thanks!
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