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Titles are over rated
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Discussion Starter · #1 ·
I am getting what I believe to be spark knock in my girlfreind's 93 Tempo.
I originaly thought it was the power steering pump, by identifying the knocking sound with a wooden dowel rod.
The car knocks at idle, and when under load (wheel locked, or heat / ac on).
It give a slight knock occasionally at idle, loud when under load, or in neutral at idle.
I have cheacked the air filter, and have cleaned the Mass air flow sensor (with elictral spray contact cleaner).
There is a second sensor at the other end of the air duct that the MAF is on.
Unless someone else has an idea, next I will clean this sensor, and re-clean the MAF.

Thanks in advance.

Scott
 

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Premium Member
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4,651 Posts
I'd look deeper into the engine for that knock.

Bottom end would be my first guess...
 

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There are a few things that can throw you off on a knock.

Is it loader when the engine is cold? - Exhaust gasket.

Tried high octane fuel and it went away? or minimized?


Edit:
Oh - 93 Tempo - scrap it - jk

I did however see a lot of those engines take a crap - lots of airflow through the valve cover (oil fill) was the first clue.
 

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Titles are over rated
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1,298 Posts
Discussion Starter · #4 ·
valve cover does not look great. I will try premium gas, and see, as far as if it does it more when cold I will drive it for a couple of days and see.
The car overall is in good shape less than 80k on it.

I don't think I mentioned, when I took the belt off and started it, the sound was gone, that is why I started looking at external components, and ruled out the concerns in the block.
I then did the back yard Mechanic's trick of listening with a dowel rod, to try to pick up the knocking. From this it sounded like it could have been the power steering, or the a/c unit. Power steering pump was more crucial, I tried that one first.

Thanks again for the help and suggestions.
 

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valve cover does not look great. I will try premium gas, and see, as far as if it does it more when cold I will drive it for a couple of days and see.
The car overall is in good shape less than 80k on it.

I don't think I mentioned, when I took the belt off and started it, the sound was gone, that is why I started looking at external components, and ruled out the concerns in the block.
I then did the back yard Mechanic's trick of listening with a dowel rod, to try to pick up the knocking. From this it sounded like it could have been the power steering, or the a/c unit. Power steering pump was more crucial, I tried that one first.

Thanks again for the help and suggestions.
Then that would make sense to be an external accessory. AC Compressor - common.
 

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skillicous
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AC and PS pumps will knock
 

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look for a wobbly pulley. Or engage the AC compressor and listen for a change. Or turn the wheel to lock load the PS pump and listen for a change
 
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