rough idle

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Mar 3, 2001 | 08:16 PM

enulsen

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rough idle

Hi, I'm looking at a 1995 F250 with the 7.3L diesel with manual transmission. It will run very rough for approx. 15 seconds if the engine is loaded slightly at idle and then the load released. Any ideas?
Thank You

Enulsen

Mar 4, 2001 | 03:57 PM

ben towe

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rough idle

My 1997 F-250 PSD does the same thing,if you rev it up (especially cold) and let off it's real rough right?Mine too.

Mar 4, 2001 | 04:28 PM

The Diesel Dude

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From: Indianapolis

rough idle

Sounds like a case of oil aeration to me. Either try changing the oil with Motorcraft (the stuff Ford recommends) or Shell Rotella (I'm sure there are other oils that meet the Ford recommended requirements but these are the ones I know do) or go to a Navistar dealership and ask for the anti-foam oil additive and see if that helps.

Mar 9, 2001 | 09:13 AM

ford4x4offrd

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rough idle

My '89 7.3L has had nothing but kendell 10w40 from napa. had good luck with it, but when you change the oil i would def. pay a little extra for the good stuff. good luck

-Jacksland

Mar 9, 2001 | 01:23 PM

The Diesel Dude

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From: Indianapolis

rough idle

On a cold engine there is, in the exhaust system, a "back pressure device" (similar to a Jake Brake) that is designed to close to facilitate warm-up faster. If this roughness you discribe is only happening with a cold engine, it could be this back pressure device is in the "on" position.