ROUGH RUNNING
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ROUGH RUNNING
I have a E-350 with a 460. It runs good until hot ( normal temp.) After that it runs really rough a idle and normal driving. New plugs and wires, EGR is good and carb is good. ANY THOUGHTS ?
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How do you know the EGR is good? The EGR is supposed to operate only when the engine is warm and while at cruising RPMs, and one that sticks open will cause a bad idle.
Many of the vacuum-operated controls are dependent on engine temperature and could be causing a vacuum leak when the engine warms up.
The DS2 ignition modules can fail when overheated but those symptoms aren't really dependent on changes in RPM, they're constant.
Many of the vacuum-operated controls are dependent on engine temperature and could be causing a vacuum leak when the engine warms up.
The DS2 ignition modules can fail when overheated but those symptoms aren't really dependent on changes in RPM, they're constant.
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I took the EGR off to see if there was any carbon stuck in it. It was clean and bench tested OK. I ran it up to temp then plugged the EGR and made no difference. Are you talking about the box on the fender well or the module in the dist. Ihave had the box go bad but at that time it wouldn't run at all.
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I have had that problem before on a different vehicle but on that one it didn't run at all. Could that cause the problem I am having? Is there anyway of testing it?
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From: Denver Metro Area, CO
You can do that as a test, too. If everything is good, the engine will stumble and possibly die when vacuum is applied to the EGR valve at idle and will resume when it's released.
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