oren1966

At higher rpms i am having power loss and popping coming from exhaust. I have pypes x pipe (no cat) and pypes off road mufflers... custom tune(93 octane).... Could this be from running rich? lean? This just started happening....... would putting octane boost in the gas cause this? I bought some cheap premium so decided to add some octane boost to fix the bad gas.... now it pops at high rpm(4500+) in 3rd 4th gear

ski

S197 GT engines do not like octane booster. It fouls the spark plugs, which is probably causing the loss of power and exhaust popping noises. Replacing the plugs is the only solution.

mynameismike65

No offense but why do people use freaking octane boost?!?!? That sh*t is nothing but trouble

Texotic

yeah... it's like saying "pretty please screw up my engine". what is the point anyway?

oren1966

I pulled 3 plugs and did not see any evidence of fouling... by the way they came out fairly easy... I was scared to death to pull them..... I am going to clean my MAF to see if that helps.... check my fuel filter..... any other suggestions?

ski

They're fouled. Replace them.

howarmat

I would agree, almost everyone that has added booster has had it happen

modaddict

yep - 100% it is either fouled plug(s) or crapped out 02 sensor both of which will happen when you use octane booster or wrong octane. (I say 'wrong' because it can also happen with too high of octane and not just 'bad' octane.