Catch-Can help needed
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Catch-Can help needed Here's a couple pics from two different angles. As you can see its just the tube from the pass. side valve cover straight to the catch can. I don't see what that can possibly accomplish. Or am I just not understanding how it works? BTW, I've never gotten even a drop out of the can and now I have oil issues. I'm not saying this is what is causing it but I'm just trying to rule this out.
You should be connecting your Catch Can in line with the PCV Valve line. I have never seen or heard anyone connect there Catch Can to that line.. It might help on the line you have it connected to, but the PCV is the one they really needs it.
Search for the other threads on "homedepot catch can". there are many other threads and pic's
BTW.. clean install you got there ! Could work on the wires a bit more on the fenders..
Search for the other threads on "homedepot catch can". there are many other threads and pic's
BTW.. clean install you got there ! Could work on the wires a bit more on the fenders..
Yeah, you have it hooked up wrong. I have a hose that comes off the PCV that goes to the top of the catch can. The lower port of the catch can goes to where the PCV used to be. It only took a few weeks before I started seeing a bunch of oil in it.
As stated, your missing the benefit of the catch can. You need to have the PCV line come off the nipple/barb on the side of the can. I can't see in the pics but is there even a side barb?
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No side barb. This is something my mechanic made for me last year. It never made sense to me but I trusted he knew what he was doing. I ran the car this way all of last season but never had any oil accumulate in the catch can. I told him I didn't think it was set up right but hey, he knows more than I do. I thought the days of "if you want it done right, do it yourself" were long over.
He just got done installing some ETP heads for me and now I have some serious smoke coming out of my exhaust. I have been going over everything in my head for a couple weeks now trying to figure out why I'm blowing smoke out the exhaust and why my dyno numbers fell flat after 5700 rpm. I've thought of several problem areas that could be the culprit and this is one of them. I'm not saying this is the sole reason I am blowing smoke out my exhaust all of the sudden but it could be a contributing factor.
BTW, where would the hose go that is currently attached to my catch can? I'm talking about the one connected to the passenger side valve cover. Where does that normally go?
He just got done installing some ETP heads for me and now I have some serious smoke coming out of my exhaust. I have been going over everything in my head for a couple weeks now trying to figure out why I'm blowing smoke out the exhaust and why my dyno numbers fell flat after 5700 rpm. I've thought of several problem areas that could be the culprit and this is one of them. I'm not saying this is the sole reason I am blowing smoke out my exhaust all of the sudden but it could be a contributing factor.
BTW, where would the hose go that is currently attached to my catch can? I'm talking about the one connected to the passenger side valve cover. Where does that normally go?
I think the hose you have on the catch can should be connected back to the throttle body. Although with no barb, you are still venting to atmosphere with that breather. You should probably just delete the PCV and run a breather on the valve cover. Your catch can isn't gonna catch anything the way it's hooked up now though. Your stock PCV system is still completely intact.
edit....i think that hose goes to the little tube coming from the bottom of the throttle body. I wish I could go look at mine, but my car is at home.
edit....i think that hose goes to the little tube coming from the bottom of the throttle body. I wish I could go look at mine, but my car is at home.
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I don't think there is anywhere else to attach to the TB. If memory serves me right and I'm looking at my picture right, there is only one hose even remotely close to the TB on the passenger side.
What if I left the catch can attached to the valve cover hose and just used the catch can as a breather and capped off everything else?
What if I left the catch can attached to the valve cover hose and just used the catch can as a breather and capped off everything else?
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Verdad Gallardo not the best pic to explain what you are asking.. but here you go https://ls1tech.com/forums/showthrea...omedepot+catch
the tube on the top of this pic is what you have connect your catch can to.. as you can see the lower hose with the PCV Valve inside if the rubber is where you need to connect your new catch can..
And now that I look at your setup.. the catch can should have two barbs on it.. in and out.. I see one coming from the valve cover going to the can.. where is other side going to..?
If you don't have it drawing some vacumn, from the intake/TB the all it is doing is venting the valve cover.. if there is pressure inside the crank case, then it would blow the pressure into the valve cover, then to the catah can and them be vented via the breather.. !? This would work for a lot of old style engine setup to handle blow by to rid crank case pressure.
the tube on the top of this pic is what you have connect your catch can to.. as you can see the lower hose with the PCV Valve inside if the rubber is where you need to connect your new catch can..
And now that I look at your setup.. the catch can should have two barbs on it.. in and out.. I see one coming from the valve cover going to the can.. where is other side going to..?
If you don't have it drawing some vacumn, from the intake/TB the all it is doing is venting the valve cover.. if there is pressure inside the crank case, then it would blow the pressure into the valve cover, then to the catah can and them be vented via the breather.. !? This would work for a lot of old style engine setup to handle blow by to rid crank case pressure.
Last edited by bczee; Mar 22, 2007 at 04:46 PM.
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That's what I was saying earlier. The catch can only has one barb on it. IMO it is simply acting as a breather for the valve cover but it just so happens the breather is at the top of a catch can. I don't even have a second spot on my TB where that particular hose is supposed to attach to. I'm so confused.
"I don't even have a second spot on my TB where that particular hose is supposed to attach to."
That's because it doesn't exist. The second hose goes to the intake, right behind the TB where you currently have the PCV plugged in to.
The hose he ran from the valve cover to the catch can is SUPPOSED to go to the inlet on the TB.
That's because it doesn't exist. The second hose goes to the intake, right behind the TB where you currently have the PCV plugged in to.
The hose he ran from the valve cover to the catch can is SUPPOSED to go to the inlet on the TB.
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Actually I looked tonight and the TB "snout" is now plugged up with a blue nut. (Look closely at picture). The nipple behind the TB is where the PCV tube is connected and that IS in the right spot. However I definitely do not have the catch can hooked up properly. I'm tempted to just plug the nipple behind the TB and run a 3/8" hose from the driver's side valve cover in the rear to the passenger's side valve cover in the rear. Then I'll leave what I have as a breather/catch-can combo. I just don't know if that breather and hose are going to be big enough.
Some of you cats are way off base. 
The hose from the throttle body to the valve cover should be connected in that manner, and needs nothing in it. Air actually flows INTO the valve cover though that line, rarely does it flow the other way. The reason is pulls its fresh air in here is so that all air entering the intake stream will be METERED air, meaning, it has passed through the MAF.
The original poster has no oil in his catchcan because air is flowing in through that filter and into the valve cover. It does this because there's a vacuum in the manifold, on the other end of the PCV hose. The only time gasses may be flowing the other way is under WOT, when the pressure is equalized on each side of the throttle body blade. This is only 1% of the time you're driving your car, unless it's a track car, and explains why there is a bit of oil/carbon on that little throttle body port.
What you can do (PewterZ28) is block off all your lines besides that one going from the valve cover to what now is a breather/catchcan. You won't have a PCV system anymore, but you will have ZERO oil consumption problems. It will be like a breather setup, but cleaner under the hood.
If you want to keep the "PCV", you need to get rid of that filter, and plug the line from the valve cover to the can back into the throttle body. Then you need to run that PCV line behind the throttle body (plugs into the manifold) into the catch can, then out and back to the manifold.
The hose from the throttle body to the valve cover should be connected in that manner, and needs nothing in it. Air actually flows INTO the valve cover though that line, rarely does it flow the other way. The reason is pulls its fresh air in here is so that all air entering the intake stream will be METERED air, meaning, it has passed through the MAF.
The original poster has no oil in his catchcan because air is flowing in through that filter and into the valve cover. It does this because there's a vacuum in the manifold, on the other end of the PCV hose. The only time gasses may be flowing the other way is under WOT, when the pressure is equalized on each side of the throttle body blade. This is only 1% of the time you're driving your car, unless it's a track car, and explains why there is a bit of oil/carbon on that little throttle body port.
What you can do (PewterZ28) is block off all your lines besides that one going from the valve cover to what now is a breather/catchcan. You won't have a PCV system anymore, but you will have ZERO oil consumption problems. It will be like a breather setup, but cleaner under the hood.
If you want to keep the "PCV", you need to get rid of that filter, and plug the line from the valve cover to the can back into the throttle body. Then you need to run that PCV line behind the throttle body (plugs into the manifold) into the catch can, then out and back to the manifold.
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Originally Posted by TheBlurLS1
The setup you have now is actually a slight vacuum leak, as air is entering your charge stream without passing through the MAF.
Ok.. we are now getting somewhere, now that we have all of the fact of what you have and what we are working with.. important facts are a good thing if one is trying to get help..
Option #1 - Get rid of the can that you have now. Remove that plug and add a barb in its place, connect the valve cover line to the barb as it should be. (as TheBlur suggested).
Then you need to get a correct two barb Catch Can and connect it inline with the PCV valve/line.
Option #2 - The other option is the keep what you have and do away with the whole PCV System (plug what is left open).. add a filter to the driver side valve cover (or Tee a line into your current catch can) and that way you will be running as a vented system or open system (with no PCV system) and that will releive any crank case pressure.. (Some have used a filter on both the oil filler neck and on the driver side PCV line location)
This can get messy if you start blowing oil out through the filter(s) (at WOT) and this is what your current catch is really design to handle. Many Race cars us this type of system as they get fined if they start blowing oil on to the track. At WOT you don't want any crank case pressure (crank case pressure will not allow the engine to rev freely at higher RPM's)
A PCV System will cause a vacumn and remove any pressure in the crank case, which is why we see oil in the intake at times, it really is sucking air and oil out of the crank case and into the intake.
Option #1 - Get rid of the can that you have now. Remove that plug and add a barb in its place, connect the valve cover line to the barb as it should be. (as TheBlur suggested).
Then you need to get a correct two barb Catch Can and connect it inline with the PCV valve/line.
Option #2 - The other option is the keep what you have and do away with the whole PCV System (plug what is left open).. add a filter to the driver side valve cover (or Tee a line into your current catch can) and that way you will be running as a vented system or open system (with no PCV system) and that will releive any crank case pressure.. (Some have used a filter on both the oil filler neck and on the driver side PCV line location)
This can get messy if you start blowing oil out through the filter(s) (at WOT) and this is what your current catch is really design to handle. Many Race cars us this type of system as they get fined if they start blowing oil on to the track. At WOT you don't want any crank case pressure (crank case pressure will not allow the engine to rev freely at higher RPM's)
A PCV System will cause a vacumn and remove any pressure in the crank case, which is why we see oil in the intake at times, it really is sucking air and oil out of the crank case and into the intake.
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Done. I just deleted my PCV system.
I plugged the rears of both valve covers and I plugged where the PCV tube connected to the intake just behind the TB. All I'm left with is the tube that goes from the pass. side valve cover to the catch-can with the breather and of course, the catch-can/breather itself.
I hope this will provide enough ventilation. How will I know if it is not?
I plugged the rears of both valve covers and I plugged where the PCV tube connected to the intake just behind the TB. All I'm left with is the tube that goes from the pass. side valve cover to the catch-can with the breather and of course, the catch-can/breather itself.
I hope this will provide enough ventilation. How will I know if it is not?