2002 Ford F150 RPM Surge

2002 FORD F-150
78,000 MILES • V8 • 4WD • AUTOMATIC
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JOHNTK2010
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F-150, 7700, 5.4 liter,
The engine rpm has begun surging upon start-up. It settles back down to idle in about 15 - 20 seconds. The surge has been getting higher over the past couple weeks. Also, the surge is higher when the engine is cold, though it also surges when hot. Any ideas concerning cause?

Thanks,
John
Apr 8, 2009 at 1:57 PM
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JACOBANDNICKOLAS
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Has the check engine light come on?
Apr 9, 2009 at 8:55 PM
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JOHNTK2010
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No, the engine light did not come on. Other problems I noticed since the surging started is light-brown exhaust at start-up; the oil reservoir was unexpectedly low; and gas mileage has dropped approximately 1 mile per gallon. Unknown if these are all related. A friend suggested an O2 sensor problem - but I would expect the engine light to come on.
Apr 10, 2009 at 2:07 PM
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JACOBANDNICKOLAS
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Sorry I didn't get back sooner. I had another extended stay in the hospital. I agree the light should have kicked on with the O2 sensor, but don't completely cancel that out.

Make sure the egr isn't leaking or sticking.
Apr 14, 2009 at 7:44 PM