Today I was talking to a buddy of mine who is a mechanic and he told me he heard that flowmasters on LS engines give the engine computer problems/engine light. Has anyone heard of this issue? I am almost to the point of running my exhaust for my LS3 in my 64 impala. Thanks in advance

 

Not sure what he is talking about. You can run any exhaust/mufflers you like. I had flowmasters on my 67 and put 7K miles on it. Not sure why a muffler would matter. I ran my 69 w open headers 8 miles to the exhaust shop with no issues.

 

This is Madness, This is blasphemy.

 

I was asking him the same question! Why would it matter? I would think you could run whatever you want as long as your 2 O2 sensors are hooked up!

 

I usually find that if the person who is claiming something cant explain why, its B.S. and I write it off. Just my .02. Eric L

 

Ask him how the computer would know what brand of mufflers you are using and why it would care. Then find a new mechanic. This sort of stuff is why I hate letting anyone else do stuff on my car, as even someone with 30 years experience might just have 3 decades of nonsense bullshit stored in his head.

 

I ran flowmasters on my swap for probably 40k miles and never had any issues with a check engine light. I hated their drone on the highway though, the car actually got much quieter on the highway when I swapped on a set of fleabay knockoff stainless magnaflows.

 

does the shop have proper ventilation? might want to make sure if the hose is on the tail pipe the shops exhaust fan is working properly.

this is what happens when you say oh im only running the car for a couple min with the garage door shut

 

I think he suggests the engine is very picky in how it will sound. Maybe you should skip the middle man and just straight up ask the engine

 

Hahahahahahaha I really like everyones response!!!! So I showed these posts to my co worker who told me this and he had no response