Running rough after heater core replacement

20

Asked by garretschoppe Jan 28, 2018 at 02:17 PM about the 2003 Ford F-150 XL LB

Question type: Maintenance & Repair

I just replaced my heater core on my 4.6L , after
removing the dash and reinstalling everything my
engine runs extremely rough. I have double
checked all plugs are connected and vacuum lines
are connected

2 Answers
20

garretschoppe answered 6 years ago

Well I originally cut the box opened to check the blend door, I'll reinstall the cut part and use adhesive to seal it. Hopefully that is the problem.

Mark helpful
20

garretschoppe answered 6 years ago

I found a large vacuum line towards the back of the engine that was not connected. I must have knocked it off when installing the hose to the heater core. Running beautifully now.

2 people found this helpful.
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