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Q: Rough idle after timing chain install run ok after 2500 rpms

asked by on December 07, 2017

Replaced valve seals timing chain and intake manifold gasket....head gaskets as well start up the vehicle has shaking rough idle but clears up after 2500 rpm.. 3000 rpm is perfect. The test drive feels like decent low rpm is crap... also would like to know if I have a wire in the wrong spot do not have a diagram for coil to plug..No smoke I'm about to set it on fire and push it over a cliff no intake vacuum leaks.....idk what to do will a off timing chain allow it to idle rough and be perfect at 3000 rpm????runs spool smooth at exactly 3000 rpm, also will this idle clear up after being driven?? It seems to (almost) disappear after warm thanks Matt 9807299880

My car has 187000 miles.
My car has an automatic transmission.

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You should check the big main vacuum line going from the PCV valve to the intake manifold. The connection at the manifold gets a hole in it and will cause problems with running at lower rpms.

Ford
Expedition
1999
V8-4.6L
running rough
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