engine knocking
Thread Starter
1st Gear
Joined: Apr 2002
Posts: 1
Likes: 0
engine knocking
I have a 82 SC with 103,000 miles on it. Just recently i began to notice some slight knocking noise when i "stomp on it". Also it only seems to happen in hot weather. I live in Los Angeles area. I had the car smogged and was wondering if a change in timing might be the problem. Anyone have any thoughts/suggestions?
RL Technical Advisor
Joined: May 2001
Posts: 11,870
Likes: 75
From: Portland Oregon
Hi:
Given the California 91 octane fuel you have and the occurrances in hot weather, you are likely experiencing some detonation and that is NOT good.
With 103K on the odometer, you probably have some carbon buildup that raises the effective compression ratio enough to make the engine more octane sensitive. You migh try some different brands of fuel to see if one works better than another for you bearing mind that winter fuels all carry more oxygenate than other times of the year.
This makes the engine run leaner than normal and you also might check your idle CO to see that its set slightly richer than spec.
By all means, lift your foot off the accelerator anytime you hear that sound so you do not buy new P/C's sooner than you need to.
Given the California 91 octane fuel you have and the occurrances in hot weather, you are likely experiencing some detonation and that is NOT good.
With 103K on the odometer, you probably have some carbon buildup that raises the effective compression ratio enough to make the engine more octane sensitive. You migh try some different brands of fuel to see if one works better than another for you bearing mind that winter fuels all carry more oxygenate than other times of the year.
This makes the engine run leaner than normal and you also might check your idle CO to see that its set slightly richer than spec.
By all means, lift your foot off the accelerator anytime you hear that sound so you do not buy new P/C's sooner than you need to.
