351 w knock

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Feb 18, 2011 | 11:10 PM

mitchelljohnson1201

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351 w knock

Hey got a 93 ford f 250 with a 351w and about a week after putting on headers i developed a knock in the engine. the motor hads about 171,000 miles but plenty of oil pressure and of course oil. I cant hear it unless i get on the throttle pretty hard either. any ideas?

Feb 19, 2011 | 03:41 PM

jimbbski

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From: Chicago area

Are you sure it's a knock? What does it sound like?
Having just installed headers are you sure that the headers are not just hitting some part of the vehicle?

Feb 19, 2011 | 05:48 PM

bashby

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From: Charles Town, W bygod Va

did you eliminate the egr when you did the headers? Could it be detonation you're hearing?

Feb 19, 2011 | 08:06 PM

fluffykins

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are you sure its not a leak?

Feb 19, 2011 | 08:39 PM

mitchelljohnson1201

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Im sure its not an exhaust leak becouse it only happens when there is a load on the motor, which brings me to the egr sensor. im buying the eliminator kit but i dont know what all to get. so far I got the block off plate and the plug in connector, not sure if i need the actuator risistors or if I need the termanal leads either? anbody know?

Feb 20, 2011 | 08:35 AM

bashby

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From: Charles Town, W bygod Va

If you think it might be detonation, retard your timing and see if it goes away. Eliminating the egr will increase the chance for detonation.

Feb 20, 2011 | 02:45 PM

restoringmy46

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From: Ashland, KY

I had a motor with headers to the samething. The knock sounded just like a rod knocking in the motor. It ended up being a header leak. The header had a bend in it but you could only tell by putting a striaght edge on it. Hope this is it and not the motor.