Coolant lines what are these for (see pic)

[redrooster524]

These two pipes rotted off my plenum. I have taken the two hoses and connected them together so there is no leakage now. (They pigtail from the heater core lines).
1. What is the purpose of these pipes in the plenum?
2. Do I get these fixed?
3. If I don't, what might happen?

99 ranger 3.0 flex

 

[adsm08]

Coolant lines running to the intake or throttle body are for a heated intake. Running coolant through the intake manifold helps emissions and cold running in cold weather by heating the air coming in. This lets the engine get out of warm-up mode faster. Once the engine is at temp it doesn't hurt anything because the intake will eventually get to that temp and bring the air in it up to the same temp the heated intake is designed to achieve. The heating system just does it faster.

Get it fixed if you want to. Or don't. Since you live in New England it might not be a bad idea to address it at some point, but it's not something I would classify as "urgent". If you lived down south I'd say forget they were ever there.

What will happen, winter MPG will probably go down and you might go through plugs a bit faster, but probably not anything significant. Maybe a check engine light, maybe not.

 

[RonD]

Yup, ^^^

Upper intake has a water jacket, so has an IN and OUT port to heat it up.
By-passing it, which is what someone did on yours, is not uncommon when one of the ports breaks.

 

[redrooster524]

Thanks for your input. Eases my mind a lot. I've been a member of this forum for a long time but never posted anything until now. That was easy. Thanks again and 73's

 

[01b3000ds]

Here's a different perspective

You now drive a modified vehicle:

http://www.therangerstation.com/forums/showthread.php?t=57879

And here's why you shouldn't fret:

http://www.therangerstation.com/tech_library/PlenumSpacers.shtml

 

[baddis]

you want another plenum? I have one off of a 00 flex fuel that I am doing a v8 swap. not sure how much shipping would be from Illinois though

 

[boozer89]

I take the plentum off, Drill and tap the holes for 1/8" pipe thread, Blow out plentum real good to get the shaving out. Hold it upside down helps. install copper 1/8"npt x 1/4" tubing compression fittings, and reattach hoses. you need a real good drill bit. as the original tubing is real tough to drill. I was able to reuse what was left of my original tube, into the comp. fitting. can post a pic if needed.