QuestionHi Dennis and thank you for your answers, very informative. Still in the dark about the tapping noise down below the engine after the plenum was changed and was it necessary to change the plenum or was that a waste...it was cracked.
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I have a 98 ford windstar, a small amount of steam comes and goes from the tailpipe, the intake plenum has been changed changed and now there's a tapping noise below the engine and still steaming, there's a small puddle of antifreeze that accumulates around one of the injectors, the scanner reads : intake manifold runner control. Haven't the slightest idea where that's located or what it does and if it will help. Thank you in advance!
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You may have an intake manifold gasket leaking into one cylinder and around the injector. The coolant pass thru the intake and heads at each end, if this is where you see coolant then the intake gasket is most likely the culprit. The 3.8 is notorious for leaks, especially head gaskets, timing cover, and intake.
The IMRC is part of the intake manifold, either vacuum or electric operation. These usually fail in the open position and can cause rough idle. But it has nothing to do with the coolant leak or steaming.
AnswerThe original plenums were actually a two piece part, some would come apart and make a knocking sound, but on the top of engine, not under it. The new plenums are sturdier as far as I know. Don't know why you now have a noise under the engine, doesn't sound related to the plenum.
There is no coolant passing thru the plenum, this has nothing to do with the plenum. The coolant CAN, however, leak from the intake mainfold itself.
