Spark Knock
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Safety Car
Joined: Apr 2002
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Spark Knock
My engine has spark knock at part to full throttle, but only when the engine is hot. When the engine is cold, there is no spark knock, and it feels like I have an extra 30 horsepower.:D What could be causing this?:confused:
I have two theories. My Q-Jet burns really rich. Since a cold engine uses more gas, the rich carb is actually a plus during warm-up. Using the cool air along with complete useage of gas, this contributes to the extra power.
Once the engine warms up, and no longer needs as much gas, some of the extra gas leaves a nice coat of carbon on my combustion chamber. This raises the compression ratio enough to cause spark knock.
My second theory is that I have a problem with the EGR valve. If this is the case, it will soon be trashed when I swap intakes.
Do these sound like good possibilities, or am I missing something?(it's very possible :crazy: )
[Modified by shotgun_000, 6:51 PM 5/31/2002]
I have two theories. My Q-Jet burns really rich. Since a cold engine uses more gas, the rich carb is actually a plus during warm-up. Using the cool air along with complete useage of gas, this contributes to the extra power.
Once the engine warms up, and no longer needs as much gas, some of the extra gas leaves a nice coat of carbon on my combustion chamber. This raises the compression ratio enough to cause spark knock.
My second theory is that I have a problem with the EGR valve. If this is the case, it will soon be trashed when I swap intakes.
Do these sound like good possibilities, or am I missing something?(it's very possible :crazy: )
[Modified by shotgun_000, 6:51 PM 5/31/2002]
