in the past 2 days to work my check engine light came on at the exact same place. doing 40 mph in 4th gear just cruising. checked the code today and it came up as code 43. which is fuel supply systems. i have a 94 LS and lately since gas is cheaper i been putting premium in instead of regular. think that could do it? fuel filter isnt too old, less then 5 thousand miles

 

it ended up being the cat converter in my last DA. it was clogged up and the backed up exhaust was throwing my oxygen sensor readings off. welded in a test pipe, reset the ecu, and it went away after months of trying everything else.

I try and bring this up when I see code 43 threads, because it's one of those things that gets overlooked.

 

yo man, my 94 ls is doing the same thing... it sputters at times when I first pull out in 1st, my gas mileage is slowly getting worse and the CEL comes on while cruising. Also while cruising and holding throttle stead, it stumbles. I'm going to get it to the garage this week because I have a huge *** headache from this thing. I'll keep in touch

 

definitely sounds like the cat converter. mine was doing the same thing. it prob wouldnt hurt to get a new oxygen sensor also if you can spare the coinage, brah.

 

hmm i never really thought of it being the cat bc i only have 1 o2 sensor and its in the header before the cat. buttt i have an answer for that because just recently i purchased a test pipe but just been too lazy to put it in. ill do that this week and letcha guys know if it still comes up