Stainless steel mufflers killed the business.

That doesn't hurt my feelings for midas

Car runs well..but SEL light came on yesterday..over week after. Wife is about 60 miles away. Car running well just SEL steady. She filled gas yesterday so maybe cap. Also one of her tires senors is out..reads --. And Discount tire rotates and never rests location.. No problem as I am old fashioned (build Hot Rods and vintage Jags) so..I check tires manually..

I'll scan when she gets home..

I got an idea ! Why don't you go to Midas ? :skull1:

Car ran fine all week..about 175 miles. No codes..rev nice. Yesterday..stumbling and poor idle. Wife 90 miles away..drove home. Codes now P0171 and P0300. Just examined and cannot see if vacuum lines leaking..or inlet tube cracked or leaking. MAF sensor ? I showed the amount of filth passed through to TB..maybe MAF damaged ?
Hurting after pulling driveshaft out of my HotRod..and hammering out U joint. But wife's car is first..!\70 year old guy..who does a lot of stuff..so aches are normal..lol
I fixed and restored the felt tube...cleaned more in TBI..using bore scope tp see in..
I am not usually a replace and hope guy..MAF cleaner first.. But code is lean cyl 1 I would not expect just cyl 1 to be due to MAF..

Old carb analog guy in digital world !
Any ideas ?

It's running well.. Cleaned MAF.w/MAF cleaner Cleaned the Throttle plate back side w/TBI cleaner saw more crap on back of throttle plate.. Good..cause I am beat. Pushing the Stude back and forth to get room to climb under and pull the driveshaft..
My cheapie reader can't clear but a friend has GM scan tool.. Ill see him manana..

I am officially retired for the night..except for babysitting 1.5 years old grandson..
Thanks folks.. Her Little Red Wagon runs again.. We'll see

The codes are lean bank one(there's only one bank), and unknown cylinder misfire. Not lean cylinder one.

Thanks...makes more sense,, Runs well now..but we'll see what occurs.. Thanks to all here your info is essential.. If this was a problem on my old sports car or hot rod the fix is direct..and I have years of experience.

Don't kill the messenger! The computer just tells you about problems it does not cause them.
The computer just is more sensitive than you. You never knew there was a tiny vac leak in the carburetted cars or the misfire once in a while that isn't really a misfire (really an incomplete fire). It worries about damaging the cat most.