Engine Knock on hard acceleration
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Pro
Joined: Jun 2004
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From: No longer in Heaven
Engine Knock on hard acceleration
took my '69 L71 (427/435 Tri-power) out for the first time on sat (seattle, nice cool day) and all was great, cruising at 70 or lower.
Car was warmed up, half hour of driving and when I accelerated hard, it knocked petty loud, and spooked me. Back at cruise 3500-4000 rpm all was well.
I am hopeful this is fuel octane problem, it's the gas that has been in the car since Jan, don't remember if I used octane boost or not.
Thoughts?
Car was warmed up, half hour of driving and when I accelerated hard, it knocked petty loud, and spooked me. Back at cruise 3500-4000 rpm all was well.
I am hopeful this is fuel octane problem, it's the gas that has been in the car since Jan, don't remember if I used octane boost or not.
Thoughts?
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The fuel shouldn't break down in 3 or 4 months. Was the tank full before you parked it? You will get more moisture in the fuel if there is alot of open space in the tank.
It could be a timing issue. I would drive it gently until you can get some fresh gas in there and see if it still does it. You may have to dial back the initial a bit.
It could be a timing issue. I would drive it gently until you can get some fresh gas in there and see if it still does it. You may have to dial back the initial a bit.
Thread Starter
Pro
Joined: Jun 2004
Posts: 561
Likes: 1
From: No longer in Heaven
Thanks for the insight. Fuel tank was only about 1/2 full, very possible condensation got in there. I'll run it empty gently then get some 93 and octane boost in there and see what happens.
