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Can anyone tell me precisely where the PCV valve is located on a 2003 DeVille Northstar 275HP regular engine? I can't find it. It was easy to find on my 99 Deville.
 

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There is no PCV valve on a 2003 Northstar to my knowlege. It was replaced by a simple orifice pressed into the cam cover fitting. The Onboard Diagnostics requirements change regularily and the PCV system came under the OBD mandate by EPA as an emission device that must be monitored by the onboard systems. So, the PCV "valve" per se was eliminated and replaced with the simple orifice. One less thing to go wrong, the onboard system is monitoring the PCV flow and operation so if it does go awry it will set a code and turn on the service engine light. Nothing to worry about with the PCV anymore. It'll even diagnose if the hose is off or leaking/cracked with age.

I don't recall exactly when but I think the PCV valve was eliminated on the 2001 model engines. Not sure but around then.
 

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'98 Buick Regal LS - '91 Caddy Seville - '87 Caddy Seville!
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no pcv??? oh well, i wonder why not?:hmm:
 

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illumina said:
no pcv??? oh well, i wonder why not?:hmm:
The engine still has a PCV (positive crankcase ventilation) system. It just doesn't have a PCV valve like the older systems did. The PCV valve is just an orifice anyway so "valve" was replaced with a fixed orifice. See the post above as for "why".
 

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Anthony Cipriano said:
The engine still has a PCV (positive crankcase ventilation) system. It just doesn't have a PCV valve like the older systems did. The PCV valve is just an orifice anyway so "valve" was replaced with a fixed orifice. See the post above as for "why".
sorry...i feel like a dummy...so basically it is one less thing you have to worry about during a tune-up...if that is the case, that is nice. thanks for setting me strait.:cool:
 

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Funny thing is you go to a auto zone or discount auto parts and they sale you a pcv valve for this year...I went crazy looking for it in my '03 deville...thanks guys.
 

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The older "rattle" PCV valve was always open, just as the newer fixed orifice style. The old style had (maybe) a weak spring and tapered plug inside which was designed to slam shut if there was a backfire, preventing flame from potentially entering the valve cover/crankcase and igniting any oil vapor. The tapered plugs were of various sizes to meter airflow for differing engine sizes, and today's orifices are sized accordingly. The PCV flow at idle is actually calculated as part of the required idle airflow circuit.

While backfire is still possible, the lack of fuel vapor throughout the intake manifold has all but eliminated the possibility of igniting the oil vapor in the crankcase.

During a cleanup/tuneup, it is not a bad idea to run a doubled pipe cleaner through the orifice. Some pretty nasty stuff passes through it........
 

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Well I'll be dipped. I find this extremely odd since there's a TSB stating that a clogged PCV valve can cause high oil consumption on these cars and even more odd that a part number CV769C is listed as the PCV valve for the 01 - 05 Northstar

I went to the dealer, got one for each car and low and behold the only thing in the cam cover is a wide open orvice as described in this thread. What the hell. So now the question is why the hell am I using 2 qts of oil every 1000 miles?
 

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2 qts per 1000 miles has to be a mechanical failure of some sort (broken or stuck ring, bad valve seal).

Have you read the "River Runs Through It" thread?
 

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Errr
 

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There was absolutely no reason to start a poll on this question - even back in 2004 (OP). Please do not chew up server space with useless polls. Thanks, CF Staff.

As posted, ALL Northstars have a PCV (Positive Crankcase Ventilation) system - the "valve" depends on year and model. Some have the older "rattle valve" while others have a fixed orifice.

All one need do is to find the large line that leaves a valve cover and enters the intake manifold - that's the vacuum - dirty air - (valve/orifice) side. The other (supply) line comes from an atmospheric air feed on or near the throttlebody - after the air filter: The clean air side.
 

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This is odd. All chain auto parts stores list and stock a pcv valve for the 2003 Seville with a Northstar. Even AC Delco's online parts catalog lists one through the 2004 model year. I purchased a new pcv valve for my mother-in-law's new acquisition, removed throttle body cover, located vacuum line, and disconnected it to find what looked like a pcv (silvery metal, in contrast to the black engine parts), but apparently pressed right in the valve cover(?) WITH NO RUBBER GROMMET! What's the deal? Any advice?
 

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Yes............ as posted several times previously, the later (roller cam) engine has no PCV "valve" as such. It's a fixed orifice. No cleaning or replacement involved. 2001 might have the older rattle valve type - it changed in there somewhere. (My 2002 has a fixed orifice)

Please read the rest of this thread. You'll find that many parts sources incorrectly list many things for the 2000 - 2004 Northstar.
 

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There is no PCV valve on a 2003 Northstar to my knowlege. It was replaced by a simple orifice pressed into the cam cover fitting. The Onboard Diagnostics requirements change regularily and the PCV system came under the OBD mandate by EPA as an emission device that must be monitored by the onboard systems. So, the PCV "valve" per se was eliminated and replaced with the simple orifice. One less thing to go wrong, the onboard system is monitoring the PCV flow and operation so if it does go awry it will set a code and turn on the service engine light. Nothing to worry about with the PCV anymore. It'll even diagnose if the hose is off or leaking/cracked with age.

I don't recall exactly when but I think the PCV valve was eliminated on the 2001 model engines. Not sure but around then.
I have to agree there is no pcv valve and yet the parts store sold me one for my 03 DeVille Northstar engine. Went to put it on and low & behold where it should go is just like you said, it is a fixed orfice like built in.
Thanks Anthony I will return this valve
2 qts per 1000 miles has to be a mechanical failure of some sort (broken or stuck ring, bad valve seal).

Have you read the "River Runs Through It" thread?
Where is that thread please, I can't locate it.
 

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Welcome to CF ..... You're replying to a thread that has been dead for almost 5 years. Most parts stores have absolutely no idea of what your engine needs/takes. You need to do some sleuthing homework before you set foot in the store.

Google "cadillac forums a river runs through it". It discusses the earlier valve cover baffle problems - not applicable to 2000 and later.

Our late 2001 and later Northstar engines don't have a PCV valve - they use a fixed orifice.

What is your problem - oil consumption ???
 

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Welcome to CF ..... You're replying to a thread that has been dead for almost 5 years. Most parts stores have absolutely no idea of what your engine needs/takes. You need to do some sleuthing homework before you set foot in the store.

Google "cadillac forums a river runs through it". It discusses the earlier valve cover baffle problems - not applicable to 2000 and later.

Our late 2001 and later Northstar engines don't have a PCV valve - they use a fixed orifice.

What is your problem - oil consumption ???
There is some oil consumption but not enough to worry. What does worry me is it blows out evidently while driving it looks like more oil loss than what actually is. I've attached some photos from under the motor I took for viewing the oil leakage. They may show you something I don't see as far as the oil leaking.
Let me start at beginning. It started with high idle and gas consumption , with occasional very high engine surge. My mechanic at the time replaced the IAC and that fixed issue. A year later kinda started same thing, replaced the IAC again but no help this time. To make matters worse had my neighbor replace my plugs and change the oil. He, the Neighbor broke the vacuum line in 3 places while trying to change plugs ( they were brittle and needed replacing anyway but this guy was spastic. It was horrible. And the oil change, the filter wasn't put on correct crimping the O-ring or gasket which ever it has. That will be easy fix.
Main issue is air leak somewhere. All vacuum lines have been replaced that run to & from rear check valve. Seems better but not right. After car runs about 5 minutes and at idle it wants to bounce slightly or jerk but not as bad as it did before ( felt like I had lifters bouncing at every light,lol) but not funny.
I've replace all plugs again when just 6 months ago was first time.
I just put new pcv valve line on while replacing the vacuum lines, that why I bought the pcv valve itself.
Ive checked the black hose looking thing, can't ever remember what it's called but I could find any cracks or leak. But I did notice the sound of air once like coming from the rear of the motor like closer toward bottom. Haven't been able to get under it to have a look yet.
I want to take it somewhere but money is tight very tight do I need to know what to have them do, otherwise I feel I will get ripped. I will get codes in it tomorrow, parts store said they can't get into our vehicle so they can't run diagnostic.
Any ideas to help me,?
Sure everything probably needs replacing last owner didn't take very good care of it before selling. And it recently turned over 200, 000 Miles
 

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I have to agree there is no pcv valve and yet the parts store sold me one for my 03 DeVille Northstar engine. Went to put it on and low & behold where it should go is just like you said, it is a fixed orfice like built in.
Thanks Anthony I will return this valve

Where is that thread please, I can't locate it.
Sorry all the pictures are gone.
 
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