Failed the CA smog test on Saturday and I am looking for some guidance on how I can *try* to clean up my emissions before heading to the shop and having a new catalytic converter installed. For context I did nothing to prepare for the first test and only drove 5 minutes across town to the test center.
Since Saturday I have changed the oil, replaced the gas cap, and checked the air filter (looked pretty new/clean to me). My plan is to run the tank to near empty then put in a few gallons of e85 or 91, drive 30-40 minutes on the highway at a high rpm, and pull right into the test center while the truck is still hot. My question to you guys is: should I use e85, 91, heet, guaranteed to pass, or something else?
I can retest for $39 so I’d like to try one of these options before heading to the shop. I know the topic has been covered but I’m interested to hear some feedback from those who have tried, whether it worked or not, and how dramatic the change in test results were. Thanks all!
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