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Discussion Starter · #1 ·
in the last couple of months, on three occassions i have heard my motor knock right after starting it. it only knocks about 2 or 3 times then quits. it doesn't do it everytime i start it. does anyone have a clue what this might be? thanks.
 

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As long as your timing is correct (and assuming the balancer hasnt slipped), it's probably good old fashioned wear...crank bearing clearances aint what they used to be
 

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Assuming you're not low on oil,

1. Could be your oil pump going south. What's your oil pressure at? Does the idiot light come on?

2. (my guess) Oil filter. What kind of oil filter are you using? I've heard of this happening with Fram filters. Change the filter, and the problem goes away. Try it, its cheap, even if you aren't running a Fram.

Or, like sharkmouth said, it might just be an old engine.
 

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Discussion Starter · #4 ·
i am using a motorcraft filter. i don't have an idiot light (although i probably qualify). i have the factory gauges that have no numbers, but the oil pressure reads high when i first start it, and reads a little low after slowing down from highway speeds. the rest of the time it's about in the middle. all in all, the oil pressure seems normal. it's time to change the oil again, anyway, so i'll buy a different brand of filter. is there one you would recommend? thanks.
 

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probably advanced...I've seen many a GM start with a momentary spark knock, probably because those yayas connect their distributor vacuum to a constant source and the starting engine doesnt like it
 

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How many miles do you have on the engine? You mentioned that the oil pressure read a little low after coming off the highway. Does the pressure ease off on the highway once the engine is at operating temperature. If so I'd guess you are having your bearing clearances adjusted as you drive. Mine behaved that way until I pulled the pan and found bits and pieces of my bearings at the bottom.
 
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