intermittent rough idle

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Oct 17, 2012 | 09:28 AM

imtryin

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intermittent rough idle

Got a '97 F250 7.3 5-speed that idles rough sometimes. Looks like the rpm drops too low when this happens. Throttle switch voltages measure good. Happens more often when it is warm outside and engine is up to operating temp. I was wondering if this is a flywheel issue? New glow plugs and cam sensor already installed. Like I said, this is very intermittent, and if I hit the throttle and bring the rpm up, the engine smooths out.
Rough idle may be an understatement- if I don't goose the throttle, it shakes the entire front end of the truck. Truck runs fine otherwise. Suggestions? Thnx.

Oct 17, 2012 | 09:48 AM

CampSpringsJohn

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From: Melbourne, Ky

You have 2 trucks that do this?

Oct 17, 2012 | 09:50 AM

CampSpringsJohn

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From: Melbourne, Ky

How long have you owned the trucks?

Miles?

Have you done any modifications to the trucks?

Last oil changes? What kind of oil?

Oct 17, 2012 | 02:29 PM

imtryin

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The 2 was a typo.
Mileage is 262k. Truck is completely stock.
Owned it for about three years.

Oct 17, 2012 | 09:53 PM

stainlessstroker95

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From: Monroe City in

Try unpluging the icp sensor and see if it runs better, and also look and see if it has oil in the connection.

Oct 17, 2012 | 10:24 PM

CampSpringsJohn

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From: Melbourne, Ky

I agree with checking the ICP plug. The mileage tells me you may be due some injector work too. You didn't say when the last oil change was, or what brand and weight oil you used. Also, when you change the fuel filter, is the filter black or dark blue? Is the diesel fuel in the filter housing discolored?