Hey folks, I replaced the heater core in my 2002 f150 last weekend. Im pretty sure i re-plugged everything I unplugged in the process of putting it back together. But now my truck seems like it missing on a cylinder or something...bad. ( It wasn't doing it before ) Spit back once going down the road, also, no heat comes through the vents when i press the accelerator but will when i let off.. Could all that be vacuum related?

Thanks for any insight

 

You could have a vacuum leak. Is it running rough at idle? I would inspect my work and double check the vacuum lines and electrical connections.

 

yes its idling rough enough to shake the truck. im about to double check everything now. thank you

 

maybe you spilled coolant into the back 2 plugs on passenger side when you pulled the hoses off the heater core?

 

One of the heater hose was leaking initially after reinstall and did indeed pour down into the spark plug hole. I replaced the coil pack and everything is fine now. Probably needs a plug, but that'll be a little later. Thanks guys