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Discussion Starter #1
do you think this rattle is detonation?
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I'm thinking I got some bad gas, i'm at 1/3 tank. Should I drive it down or get some 100 octane and put it in..
I always go 91 @ COSTCO?
 

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01lexusON19s said:
dude, that almost sounds like a valve knocking...not detonation...
I would second that
 

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costco gas is bullshit gas and you should NOT use it. You are in california, your best bet is to only use Mobil gas. It has the least additives and usually isnt screwed up.
 

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forget the gas at this point...does the sound go away at higher rpms or is it always there? try reving it slowly while in park up to about 3k or so and see if it goes away. if it goes away it is detonation, if it doesn't you have problems.
 

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Discussion Starter #8
o1lexusON19s:
it goes away..
so if it goes away at high rpms its detonation? shouldn't it get worse in higher rpms?
Malek:
Mobil huh? I'll try that....

so far, suggestions are valve knocking... I'll park it until I can get the shop to check it out..
 

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definitely not detonation. Detonation sounds like someone is dropping marbles on your valve cover - not like someone put a helicoptor under your hood.........

Sounds more like a spun bearing to me. Try to stick your head in the wheelwell and see if it's louder near the bottom end. If so, time to rebuild.
 

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rllinghardis300 said:
o1lexusON19s:
it goes away..
so if it goes away at high rpms its detonation? shouldn't it get worse in higher rpms?
Malek:
Mobil huh? I'll try that....

so far, suggestions are valve knocking... I'll park it until I can get the shop to check it out..
you're right, i had it backwards.
 

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i also noticed you're supercharged...it probably is detonation, make sure you're a/f mixture is right.
 

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i dont know what that sound is, but it sounds like shit!

where do you think the sound is coming from? head, block, S/C?

-Brett
 

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Discussion Starter #13
sounds like its coming from the block but it doesn't get any louder with accelleration..
i'm going to park it untiil i can get it up to the shop.
 

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That is metal on metal contact. Sounds like a spun rod bearing, rod knock, sticking valves, or other head damage? Is the motor starved for oil? Have you checked compression on any cylinders yet?

-Dan
 

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It sounds like supercharger whine.

Why do you guys say detonation, valve knocking and shit? I didn't hear any of that.
 

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Discussion Starter #18
Super:
I'm going to disconnect the blower today and start the car. See if that goes away.
If the noise goes away, it probably is the blower. If so then I'm going to have a talk with Vortech as it was just sent in for a rebuild. :( after my fire incident.
 
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