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Discussion Starter · #1 ·
Last nite I had my buddy, who works for a Chevy Dealership, program a new key for me so I can use a remote starter, he owns his own Tech II. Anyway, I offered to let him take it for a spin. When I told him to punch it,(motor wasn't cold), he and I both heard what we feel is detonation,(popping thru the exhaust under acceleration). Has anyone else had this problem?. I am using premium gas (Mobil or Shell).
 
G

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cant overrev in anygear LMFAO.. it will bounce off the limiter when burning out and in neutral.. and under load it will bog the hell out yo car... :willy: :party:
 

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detonation is not heard through the exhuast (tail pipes that is) but under the hood. it sound as if one of the pistons is loose and rattling that chances are you won't even hear it becuase the computer will retard the timming so fast if you do hear it it will only be for a second or two.
 

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Detonation sounds like a can of spray paint with metal balls inside. It's more prevalent at WOT.
Many people describe the sound in different ways.
I bet what you're hearing is the natural "cackling" of the exhaust when you let off the gas. Which is at the opposite time that detonation happens (when you are ON the gas).
If you don't have a supercharged/turbocharged engine, the chances that you're getting detonation are VERY VERY slim. The computer is designed to prevent that. GNX was right, the computer would be pulling timing so quickly that you'd never even be able to hear the detonation.
I'll bet'cha dollars to donuts that you're hearing something else. If you want to double-check, you can always go on down to your local tuner/dyno-shop, and have him put an O2 sensor on your exhaust (or inside your tailpipe), then get a good tune. It's worth the money anyway. You'll pick up a couple of extra horsepower, and your worries about detonation can be relieved.
Until you can get the tune, if you're worried that it is detonation (despite my EXPERT opinion that it's not haha), use premium fuel and don't go WOT if you can help it.
Whenever you figure out what it is, please post back here, I'm interested to know what you find out.
 

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Yep, it's very important that you post back, that way if anyone else runs into the same problem, they can see what you did to resolve it. :)

Also, bad gas won't cause detonation. It'll cause your car to run like crap, but I *SERIOUSLY* doubt that you'll ever hear any detonation. That computer works SO quickly that it'll yank timing before your brain can diagnose, cross-reference and process the sound.
 

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Well, it sure beats getting out of the car and turning those dang screws on the carburetor every time the temperature changes a couple of degrees! :lol:
 

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Discussion Starter · #17 ·
baron_iv said:
Detonation sounds like a can of spray paint with metal balls inside. It's more prevalent at WOT.
Many people describe the sound in different ways.
I bet what you're hearing is the natural "cackling" of the exhaust when you let off the gas. Which is at the opposite time that detonation happens (when you are ON the gas).
If you don't have a supercharged/turbocharged engine, the chances that you're getting detonation are VERY VERY slim. The computer is designed to prevent that. GNX was right, the computer would be pulling timing so quickly that you'd never even be able to hear the detonation.
I'll bet'cha dollars to donuts that you're hearing something else. If you want to double-check, you can always go on down to your local tuner/dyno-shop, and have him put an O2 sensor on your exhaust (or inside your tailpipe), then get a good tune. It's worth the money anyway. You'll pick up a couple of extra horsepower, and your worries about detonation can be relieved.
Until you can get the tune, if you're worried that it is detonation (despite my EXPERT opinion that it's not haha), use premium fuel and don't go WOT if you can help it.
Whenever you figure out what it is, please post back here, I'm interested to know what you find out.
Thanks for the input. The noise is definately coming from the exhaust under acceleration only....(scratches head). It sounds tinny, and I'm only using premium gas Mobil or Exxon or Shell. Depends where I am when I'm low on fuel. Could it possibly be the restrictions in the pipes from the factory where they crimp it for clearance? These areas are crimped severely.
 
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never know........worse things have been found wrong on new cars. Just pull em to see what they look like. Maybe one has a broken electrode.
 
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