vac leak/valve cover/ o2 sensor
08-27-2013, 11:38 AM
#1
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vac leak/valve cover/ o2 sensor So just the other day I changed my pass valve cover gasket with a cork gasket, and applied some rtv to keep it in place. I tightened it correctly and reconnected everything. But now the car seemed to idle slightly higher then usual, and there's change in sound idle as well to where it sounds "grumpier". Acceleration is fine, it's just really when it sits and idles. Shbox has said it was most likely a vac leak, but i thought id ask addl opins on this. I'm also having a pending P0153 code, which points at an 02 sensor, so debating on changing it out. I need to have this all fixed soon so I can get it smogged, and 02 is the last thing to complete on dtc. Should i swap back to a rubber vc? I'm still looking for a leak and i think its the air check valve on The pass side, specifically the lower pipe going to the block. Any suggestions? Thanks!
08-27-2013, 12:57 PM
#2
I would use the FelPro rubber VC gaskets.
the air check valve goes on a tube that crosses over to the other side of motor into another check valve, not the "block"
inspect for exhaust manifold leaks/cracks and also confirm you have no vac lines on the intake manifold you may have knocked off during VC gasket replace and none of them are cracked.
the air check valve goes on a tube that crosses over to the other side of motor into another check valve, not the "block"
inspect for exhaust manifold leaks/cracks and also confirm you have no vac lines on the intake manifold you may have knocked off during VC gasket replace and none of them are cracked.
08-27-2013, 01:24 PM
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I would use the FelPro rubber VC gaskets.
the air check valve goes on a tube that crosses over to the other side of motor into another check valve, not the "block"
inspect for exhaust manifold leaks/cracks and also confirm you have no vac lines on the intake manifold you may have knocked off during VC gasket replace and none of them are cracked.
the air check valve goes on a tube that crosses over to the other side of motor into another check valve, not the "block"
inspect for exhaust manifold leaks/cracks and also confirm you have no vac lines on the intake manifold you may have knocked off during VC gasket replace and none of them are cracked.
08-27-2013, 02:56 PM
#4
the cork gaskets are "OK" if they are in and not leaking.
with your headers, Fel Pro gskets, stage 8 bolts they should be fine. didn't know if you had stock exhaust manifods that could be cracked or broken manifold bolt.
confirm the conection of header and CAT pipe is secure and no exhaust leak is causing the 02 to read bad.
Yes your 02 itself certainly could be bad if you have confirmed no vac leaks. 0153 is bank 2, sensor 1 which is PS front 02. you could replace 02 or swap to the other side to see if te code migrtes to that side
since your issue started when you changed VC gasket, take a real close look at the vac fittings/lines on the side you did the gasket on, or both sides. something as simple as the vac line for HVAC controls not on or the elbow cracked will cause leaks
I have not use "brake cleaner"...did carb cleaner way back in the day. spraying flamabile on a hot motor/exhaust is not recomended. Smoke is best but not a cheap piece of gear. There is a poor mans "cigar" smoke trick, google for the youtube vid
with your headers, Fel Pro gskets, stage 8 bolts they should be fine. didn't know if you had stock exhaust manifods that could be cracked or broken manifold bolt.
confirm the conection of header and CAT pipe is secure and no exhaust leak is causing the 02 to read bad.
Yes your 02 itself certainly could be bad if you have confirmed no vac leaks. 0153 is bank 2, sensor 1 which is PS front 02. you could replace 02 or swap to the other side to see if te code migrtes to that side
since your issue started when you changed VC gasket, take a real close look at the vac fittings/lines on the side you did the gasket on, or both sides. something as simple as the vac line for HVAC controls not on or the elbow cracked will cause leaks
I have not use "brake cleaner"...did carb cleaner way back in the day. spraying flamabile on a hot motor/exhaust is not recomended. Smoke is best but not a cheap piece of gear. There is a poor mans "cigar" smoke trick, google for the youtube vid
08-27-2013, 03:49 PM
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Awesome tips sir. I do have an issue after recently installing new catalytic converters, they are the direct fit cats by magnaflow. The driver side cat, from what my installer told me, may leak because of the supplied gasket. He had said to get a "better" gasket, but i couldn't imagine anything better then a magnaflow gasket. Are there performance gaskets for the driver side? Or can this be resolved with another method, because the part of the cat and header are bolted pretty tight. I did remember before the gasket on that side get pretty burnt from the heat. If that makes any sense.
08-27-2013, 05:24 PM
#6
if your installer for the CAT said "it may leak because of the supplied gasket"...wtf.
I don't have a F-body but it sounds like the connection to header is not ball socket but a flat 3 hole flange type. the gasket supplied may be crap. I would suspect just buying a "OEM" type at NAPA or some place like that would be sufficient.
if you have a exhaust leak upstream of the front 02's, than the 02 see's air and PCM dumps fuel. You will fail smog if this is happening.
from this side of the internet I don't know what a VC gasket replace would have anything to do with your code other than during the process you knocked off a vac line.
The potential FU gasket on the CAT would certainly cause the code. Gasket should only be a few $,
I don't have a F-body but it sounds like the connection to header is not ball socket but a flat 3 hole flange type. the gasket supplied may be crap. I would suspect just buying a "OEM" type at NAPA or some place like that would be sufficient.
if you have a exhaust leak upstream of the front 02's, than the 02 see's air and PCM dumps fuel. You will fail smog if this is happening.
from this side of the internet I don't know what a VC gasket replace would have anything to do with your code other than during the process you knocked off a vac line.
The potential FU gasket on the CAT would certainly cause the code. Gasket should only be a few $,
08-27-2013, 06:43 PM
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if your installer for the CAT said "it may leak because of the supplied gasket"...wtf.
I don't have a F-body but it sounds like the connection to header is not ball socket but a flat 3 hole flange type. the gasket supplied may be crap. I would suspect just buying a "OEM" type at NAPA or some place like that would be sufficient.
if you have a exhaust leak upstream of the front 02's, than the 02 see's air and PCM dumps fuel. You will fail smog if this is happening.
from this side of the internet I don't know what a VC gasket replace would have anything to do with your code other than during the process you knocked off a vac line.
The potential FU gasket on the CAT would certainly cause the code. Gasket should only be a few $,
I don't have a F-body but it sounds like the connection to header is not ball socket but a flat 3 hole flange type. the gasket supplied may be crap. I would suspect just buying a "OEM" type at NAPA or some place like that would be sufficient.
if you have a exhaust leak upstream of the front 02's, than the 02 see's air and PCM dumps fuel. You will fail smog if this is happening.
from this side of the internet I don't know what a VC gasket replace would have anything to do with your code other than during the process you knocked off a vac line.
The potential FU gasket on the CAT would certainly cause the code. Gasket should only be a few $,