2004 Sebring 4 cyl questions

A couple of questions/comments to the group on my wife's 2004 Sebring with
2.4L:

1) When I got it home, I was looking under the hood and noticed that the air
intake snorkel attached to the upper rad mount had a WIRING HARNESS running
right through the middle of it. Given that the snorkel inlet is only about
4" x 3/4", this is a significant restriction. Moved it right out of the way
and the car seems much happier. Got me to thinking though - given the
redesigned head and intake that is tuned for low-end torque, is there
anything I can do to "uncork" the intake on this car for a little better
high-end? It's kind of too bad they messed with it - I swear that our
Company pool car 1998 Breeze has more snap.

2) Anyone know what the metal plate/cover that sits on the intake manifold
downstream of the throttle body is for? It looks like a mount for a
blow-off valve?

3)There are two hoses that connect to the cam cover. One has what looks
like the PCV valve in it and connects to the throttle body, but the other
connects directly to the intake snorkel downstream of the air filter. Given
that this hose has no restrictions, what good is the PCV valve?

4) Anything else I should know about this motor?

Thanks.

Jeff Falkiner
95 neon - currently waiting for open-heart surgery to fix a coolant breach
99 Intrepid - the Green Monster
04 Sebring - the Silver Bullet

 

Jeff... it is what it is.. a 4 cyclinder in a Sebring

Just enjoy the ride.. if it was horsepower you were looking for
should have gotten a Crossfire or a 300C with a Hemi!


stan

 

The two hoses are at totally different points in the intake system. The
PCV hose is on the engine side of the throttle body. The breather tube
is on the upstream side of the throttle body. You have to think in
terms of what the vacuum levels are at those two points relative to the
crankcase pressure situation at any given throttle and engine operating
conditions to figure out what the flows will be. During throttle-closed
conditions, air flows into the breather tube from the snorkel (IOW, a
small part of the idle air is tapped off the snorkel and ends up back in
the intake plenum thru the PCV valve and hose - same starting point,
same end point, one took a detour thru the crankcase).

During WOT, you have less vacuum in the intake plenum and more in the
snorkel (than you have at idle), but both hoses are venting air to the
intake from the crankcase while it is generating maximum blow by (which
would otherwise tend to pressurize the crankcase).

The PCV valve blocks any positive pressure pulses from backfires feeding
back into the crankcase. The partial blocking by the throttle body and
the more open nature of the snorkel back thru the air filter isolate
that hose from major effects of backfires (making it into the crankcase).

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
adddress with the letter 'x')

 

Yes, but I would have been asking the same questions about the Hemi -
"what's this" and "can I economically get a bit more power".

Cheers!
Jeff

 

Thanks Bill. As usual your comments are well thought out. Makes total
sense once someone explains it. Had I thought about it more before putting
fingers to keyboard (a common affliction in this group), I probably could
have figured it out. It's still good to know that I can some here and get
my questions answered. Having been a lurker and occasional poster for
years, I know there are some good knowledgeable posters here.

Jeff Falkiner
95 neon - currently waiting for open-heart surgery to fix a coolant breach
99 Intrepid - the Green Monster
04 Sebring - the Silver Bullet

 

The sebring is significantly larger and therefore heavier so i would expect
it to seem and feel more sluggish.

That plate is probably a cover for where the EGR valve wouild sit if your
engine was equipped. Rather than run off 2 different castings its more
economical to produce one and cap the one which doesn't need the EGR valve
(non california).