pcv catch can and problems!
Thread Starter
Drifting
Joined: May 2003
Posts: 1,551
Likes: 0
From: salt lake city UT
pcv catch can and problems!
this is with an ati daul int , single fan and amw catch can setup.
1st problem i noticed is, driver side valve cover pcv hose (closest to winshield, about nickle size) either came loos or was blown loos and oil was all over the place.
2nd there is a screaching noise that happens after the car is running for a min or two ,that go's away if you take off the oil cap...seems to be pressure in the system.
3rd, i noticed the car was running and sounding off, after a fill up from a dif gas station. muffled missing sound....30% reduction of power. i don't no if its the pcv/ catch can set up or gas related probs or both.
4th the car ran fine for 3 weaks with the same pcv set up....why prob now?
This is my pcv setup= a)valve covers teed by factory are going into the top of amw catch can.
b)exiting out the side of can and giong into check valve and into side of manifold behind throttle. body.
c)pass, front v line is capped.
d) ati air box line is capped.
e) i was told to take off the valve cover breather and put the oil cap back on.
Thanks for any input!
1st problem i noticed is, driver side valve cover pcv hose (closest to winshield, about nickle size) either came loos or was blown loos and oil was all over the place.
2nd there is a screaching noise that happens after the car is running for a min or two ,that go's away if you take off the oil cap...seems to be pressure in the system.
3rd, i noticed the car was running and sounding off, after a fill up from a dif gas station. muffled missing sound....30% reduction of power. i don't no if its the pcv/ catch can set up or gas related probs or both.
4th the car ran fine for 3 weaks with the same pcv set up....why prob now?
This is my pcv setup= a)valve covers teed by factory are going into the top of amw catch can.
b)exiting out the side of can and giong into check valve and into side of manifold behind throttle. body.
c)pass, front v line is capped.
d) ati air box line is capped.
e) i was told to take off the valve cover breather and put the oil cap back on.
Thanks for any input!
Last edited by master blaster; Nov 1, 2004 at 11:34 AM.
Melting Slicks
Joined: Jan 2003
Posts: 3,251
Likes: 4
What kind of check valve are you using? What is the cracking pressure? Post a pic if you can. You are either pressurizing the crank from the intake/PCV or broken rings on the piston. I hope it's the first one. #7 is the culprit most offen from what I understand and that would make sense if the screech is coming from there as well.
Last edited by drcoffee; Oct 31, 2004 at 02:58 PM.
Thread Starter
Drifting
Joined: May 2003
Posts: 1,551
Likes: 0
From: salt lake city UT
Originally Posted by drcoffee
What kind of check valve are you using? What is the cracking pressure? Post a pic if you can. You are either pressurizing the crank from the intake/PCV or broken rings on the piston. I hope it's the first one. #7 is the culprit most offen from what I understand and that would make sense if the screech is coming from there as well.
Melting Slicks
Joined: Jan 2003
Posts: 3,251
Likes: 4
What is the part number of the check valve. If the cracking pressure is too high it may never open under vacuum.
Does it screech at idle with oil filler cap on? If so try keeping the cap on and remove the check valve from the line. You only need it when in boost and testing it in the driveway won't produce boost. Then tell us if the screech still persists.
Does it screech at idle with oil filler cap on? If so try keeping the cap on and remove the check valve from the line. You only need it when in boost and testing it in the driveway won't produce boost. Then tell us if the screech still persists.
Melting Slicks
Joined: Jan 2003
Posts: 3,251
Likes: 4
Originally Posted by master blaster
the check valve is the mc master car that was rec from the forum. i aslo have a forged motor.screech went away when oil cap was removed and breather was put on....but i think no oil vapors are geting in can because the breater is causing a no vacume situation.
What was the part number of the McMaster carr check valve? I'd like to know what the cracking pressure is.
Thread Starter
Drifting
Joined: May 2003
Posts: 1,551
Likes: 0
From: salt lake city UT
Originally Posted by drcoffee
First, remove the check valve from the line and tell us if the screech persists. if it does you are pressurizing the crank case and the PVC is not the culprit. Because the PCV connection on the driver's side is less likely to pop than the oil dip stick, I'm guessing the piston rings are shot.
What was the part number of the McMaster carr check valve? I'd like to know what the cracking pressure is.
What was the part number of the McMaster carr check valve? I'd like to know what the cracking pressure is.
• Cracking Pressure: 0.3 psi
Last edited by master blaster; Oct 31, 2004 at 08:56 PM.
Melting Slicks
Joined: Dec 2003
Posts: 3,315
Likes: 17
From: Near Jacksonville Fl.
Originally Posted by master blaster
McMaster carr # 7775K52 ($9.97)= the one drcoffee rec..a while back.• Maximum Pressure: 1000 psi
• Cracking Pressure: 0.3 psi
• Cracking Pressure: 0.3 psi
The line from the catch can should go to the port on the manifold behind the the TB. on the pass. side with the check valve in between.
Then you need a fresh air intake for air movement so I use the line on the front of the rt. vc down to the ATI air filter with a CH. air liquid seperator in it. (diriction of flow is up to you, I prefer the C/H flow)
Then add a breather cap to the oil fill and your PCV system will function all of the time whether your under boost or normal driving.
The way your hooked up now will never vent your cc.
Melting Slicks
Joined: Jan 2003
Posts: 3,251
Likes: 4
Originally Posted by corvettebob1
Your problem is the routing of the lines.
The line from the catch can should go to the port on the manifold behind the the TB. on the pass. side with the check valve in between.
Then you need a fresh air intake for air movement so I use the line on the front of the rt. vc down to the ATI air filter with a CH. air liquid seperator in it. (diriction of flow is up to you, I prefer the C/H flow)
Then add a breather cap to the oil fill and your PCV system will function all of the time whether your under boost or normal driving.
The way your hooked up now will never vent your cc.
The line from the catch can should go to the port on the manifold behind the the TB. on the pass. side with the check valve in between.
Then you need a fresh air intake for air movement so I use the line on the front of the rt. vc down to the ATI air filter with a CH. air liquid seperator in it. (diriction of flow is up to you, I prefer the C/H flow)
Then add a breather cap to the oil fill and your PCV system will function all of the time whether your under boost or normal driving.
The way your hooked up now will never vent your cc.
Here is a dumb idea but just for giggles make sure the check valve air flows TO the intake.
Last edited by drcoffee; Nov 1, 2004 at 11:10 AM.
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Thread Starter
Drifting
Joined: May 2003
Posts: 1,551
Likes: 0
From: salt lake city UT
i wanted to clarify that the lines exiting out the side of can and are giong into check valve and into side of manifold behind throttle body.
(not the throttle body, like stated befor...i edited the first post)
I took of the check valve and put the oil cap on and the screech noise went away.
I looked in the air bridge and it looks to have more oil vaper residue than before....i may just be parinoid about that!
I noticed the metal tube under the throttle body has nothing on it...is that ok
One question is when you remove the factory PCV valve where is that...i am not sure if that was removed in the past...is it the black tube attachment that goes into the manifold? the reason i am wondering,is with the check valve and the pcv valve both on...it is causing to much restriction....that why i hope the pcv valve was off!
what do you recomend...next?
(not the throttle body, like stated befor...i edited the first post)
I took of the check valve and put the oil cap on and the screech noise went away.
I looked in the air bridge and it looks to have more oil vaper residue than before....i may just be parinoid about that!
I noticed the metal tube under the throttle body has nothing on it...is that ok
One question is when you remove the factory PCV valve where is that...i am not sure if that was removed in the past...is it the black tube attachment that goes into the manifold? the reason i am wondering,is with the check valve and the pcv valve both on...it is causing to much restriction....that why i hope the pcv valve was off!
what do you recomend...next?
Last edited by master blaster; Nov 1, 2004 at 01:36 PM.
Melting Slicks
Joined: Dec 2003
Posts: 3,315
Likes: 17
From: Near Jacksonville Fl.
Originally Posted by master blaster
i wanted to clarify that the lines exiting out the side of can and are giong into check valve and into side of manifold behind throttle body.
(not the throttle body, like stated befor...i edited the first post)
I took of the check valve and put the oil cap on and the screech noise went away.
I looked in the air bridge and it looks to have more oil vaper residue than before....i may just be parinoid about that!
I noticed the metal tube under the throttle body has nothing on it...is that ok
One question is when you remove the factory PCV valve where is that...i am not sure if that was removed in the past...is it the black tube attachment that goes into the manifold? the reason i am wondering,is with the check valve and the pcv valve both on...it is causing to much restriction....that why i hope the pcv valve was off!
what do you recomend...next?
(not the throttle body, like stated befor...i edited the first post)
I took of the check valve and put the oil cap on and the screech noise went away.
I looked in the air bridge and it looks to have more oil vaper residue than before....i may just be parinoid about that!
I noticed the metal tube under the throttle body has nothing on it...is that ok
One question is when you remove the factory PCV valve where is that...i am not sure if that was removed in the past...is it the black tube attachment that goes into the manifold? the reason i am wondering,is with the check valve and the pcv valve both on...it is causing to much restriction....that why i hope the pcv valve was off!
what do you recomend...next?
Drcoffee makes a good point in making sure the flow direction is correct on the check valve, but you said the car ran fine for 3 weeks?
The metal tube under the tb is ok to have nothing on it since it's normally connected to coolent. (sounds like someone did a coolent bypass).
What I don't understand is the oil in the airbridge
Do a compression test! This dosen't sound good
Melting Slicks
Joined: Jan 2003
Posts: 3,251
Likes: 4
You PM'd me and I think this is important. The question was; if you disconnect the PCV line do you get vacuum from the intake port? A: yes
Also do you feel air blowing out the PCV line while disconnected? A: yes
"i dissconected the pcv valve behind the throttle body and there is vacume.
I did get air flow from the catch can exit line...is that bad?
How do i check if the rings are bad?"
Yes this shows that you have a pressurized crankcase at idle and that is serious. Check the engine oil for color, you may have bad rings, bad head gasket, etc. You need a compression test.
I'd call a tuner close by to trouble shoot the problem.
Good luck.
Also do you feel air blowing out the PCV line while disconnected? A: yes
"i dissconected the pcv valve behind the throttle body and there is vacume.
I did get air flow from the catch can exit line...is that bad?
How do i check if the rings are bad?"
Yes this shows that you have a pressurized crankcase at idle and that is serious. Check the engine oil for color, you may have bad rings, bad head gasket, etc. You need a compression test.
I'd call a tuner close by to trouble shoot the problem.
Good luck.
