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Discussion Starter · #1 ·
I've heard running anything less than premium gas can cause detonation with the S197. I run 87 usually all of the time, at least for the past year. Before that I always ran 93. But times are tough, ya know?!

Can running the cheap stuff cause knockin in the cylinders? And if so, if I run 93 every so often, will this eliminate the knock?

Early this morning I drove to my father's house, several blocks away, and shut the car off. There was a definitive knock sound; I thought it was a neighbor knocking on a door. My father was beside the car, and said "what the hell was that? Sounds like your car wanted to keep running..."

I figured it was just the grumble from the Loudmouths... Any ideas, fellas?
 

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5$ a fill up isnt going to break you, but will break your car.;)

IF your going to run crap gas, get a dyno tune w/ it to make sure you dont ruine your car.
 

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Discussion Starter · #3 ·
But that's what I'm saying. Can cheap gas really hurt your car? I just find that hard to believe, but maybe I'm ignorant to the truth here...
 

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Your PCM will pull timing to run 87. That just sounds like you got some **** gas. No worries. Before the KB, I burned midgrade, and it seemed to do best on that. Throw in a little Shell or Chevron and you should be fine.
 

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But that's what I'm saying. Can cheap gas really hurt your car? I just find that hard to believe, but maybe I'm ignorant to the truth here...
Not so much cheap gas, but stale gas...We have garbage for gas up in N.D. and my car won't even idle well on it, and it's because there are only a handful of cars in town that even use premium...just go to a station that has a lot of traffic through it...that keeps the turnover high and helps with making sure you're not burning varnish.
 

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REEEEEEEEEEEEEEEPSSSS!!!!! ;)


Let us know if it keeps up...BTW what brand of gas were you using when it started pinging like that?

EDIT: Doesn't have to be premium...just fresh...save your money and get the midgrade, trust me.
 

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Your knock sensor is designed to work with the PCM to retard the timing when a knock is detected and basically it retards the timing to stop the knock. If the engine continued to run when you shut it off, that is dieseling (run-on), if it's dieseling it basically means the combustion chamber of the cyl. head is staying too hot from either some bad gas or really carboned up. My advice, stick with the premium at .20 extra per gallon it's not worth piston damage.
 

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Discussion Starter · #9 ·
I agree kraigster.

Basically I heard it for a quick moment after I shut the car off. Maybe four "knocks".
 

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Cool. I'll fill up with some premium Shell and go from there. Thanks Grabber.

Shell has ALOT of alcohol... Chevron 93 or Sunoco 94
 

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Discussion Starter · #11 ·
I usually only use BP because they're literally on my street. And across the street from my work.

Sunoco is kind of close, but I'm sure I can give it a shot sometime, maybe once a month, ya know? It's worth a try.
 

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I usually only use BP because they're literally on my street. And across the street from my work.

Sunoco is kind of close, but I'm sure I can give it a shot sometime, maybe once a month, ya know? It's worth a try.
get to a dyno, get a tune for the cheap stuff, and one for the sweet... ALOT cheaper than where you are heading;)

AND, car will run ALOT stronger with the cheap stuff, if its tuned for it!
 

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Discussion Starter · #13 ·
And I can do this before I get a handheld tuner? I can have some re-tune the car at the dyno?
 
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