after catch can install car smokes at idle and 1st gear

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drifting1two40
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after catch can install car smokes at idle and 1st gear

Post by drifting1two40 »

as the subject says it smokes only after it warms up at idle, when you bloop the throttle, and when you drive in first gear then put it in neutral and come to a stop it tends to smokes on and off...never just constant smoke. all this started to happen after I installed an ebay catch can. one hose goes from the valve cover to the catch can then from the catch can to the pvc valve. so this morning I decided to remove both hoses going to the catch can and I can no longer get the car to smoke. so basically the hoses are to atmosphere. any idea why this is happening? is the crankcase building to much pressure forcing oil into the cylinders to make it burn..because it is oil that is burning.

info on my setup
ka24det
isis t25 replacement
sr smic
-3an feed line

rebuilt motor 4600 miles ago a good 1200 is drifted on. daily driven when im not in my daily. about 50-60 miles on the turbo. I have been babying the turbo to try and not prematurely blow out turbo seals
gearhead290
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Re: after catch can install car smokes at idle and 1st gear

Post by gearhead290 »

Does your catch can have a breather or a vent on it?
ICEMAN.KCMO
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Re: after catch can install car smokes at idle and 1st gear

Post by ICEMAN.KCMO »

It is smoking because your crankcase is no longer operating under a vacuum. You need to hook one end of the catch can to the valve cover and the other to the turbo inlet. This way it will draw the gasses out of your crank case. As for the PCV valve, I haven't decided what to do with that. it was hooked up in the factory location and i never had any issues with it. I figured as long as the pcv valve isn't letting boost pressure back into the crankcase, it should be fine.

On a side note, do some research on google about engine crankcases operating under a vacuum.
Steve.
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MadMax
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Re: after catch can install car smokes at idle and 1st gear

Post by MadMax »

Bringing this back to life quick/Jacked.. Similar issue here..

Fully built KA-T just getting it buttoned up here. I have a maf setup recirculating DV. Two Catch Cans that vent to atmosphere. One is from the valve cover. The second is from the pcv valve (intake manifold properly sealed). I am smoking oil big time, which I believe is from access crank case pressure. My turbo drain line is not draining properly or at all under this pressure, and building up in the turbo, pushing it past the seals. It actually bubbles out inbetween the drain flange gasket on the turbo from the pressure. The turbo is freshly rebuilt so I want to figure this out before (if not already) its too late on those seals.

From reading on here I have seen that I can either run a closed two port catch can from the pcv valve - catchcan - pre turbo after the MAF to get vacuum to pull pressure out the pcv, filter crap floating with it, and then cleaner air into the turbo. This is solution A I am leaning towards, but I want to make sure my pcv valve is not stuck closed.

However I wanted to know if anyone has tried this : if I replace the pcv valve with a straight barbed fitting (so it is open all the time) going to a vented catch can. Would that open fitting in place of a pcv valve be enough to relieve pressure from the crank case or do I NEED vac to pull it out?

Any help is appreciated, as there is a lot of incorrect info out there, and I just want to avoid wasting more of my time doing other tests.
ICEMAN.KCMO
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Re: after catch can install car smokes at idle and 1st gear

Post by ICEMAN.KCMO »

I haven't tried option b, i am currently running what I described above. The reason why it works so well, is the suction from the turbo will create a vacuum in the catch cans / crankcase. If you vent your PCV to the catch can, & a cat scan to the atmosphere, there will still be a pressure buildup in your crankcase. Nothing will be helping that pressure escape.

Here is how will my setup works, I had three cracked pistons on my 194000 mile engine. It only smoked a little, and only enough to make me think it was the normal valve guide seals. The only time it would smoke, was a little bit after idle, and in boost. When I get my car back together, I will post a picture of the routing. I'm not completely sure what I'm going to do with my PCV valve. I thought about venting it into the exhaust and making the "injection tube"(for lack of a better work) that creates a venturii effect.
Steve.
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MadMax
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Re: after catch can install car smokes at idle and 1st gear

Post by MadMax »

@ICEMAN.KCMO I'll give the known working option a go here tonight, I'm pretty sure it will be the best route like you said. Thanks for the response!
adamky
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Re: after catch can install car smokes at idle and 1st gear

Post by adamky »

drifting1two40 wrote:all this started to happen after I installed an ebay catch can. one hose goes from the valve cover to the catch can then from the catch can to the pvc valve.
How many ports does the catch can have on it? Does it have the two ports plus a third port for a breather filter?
Wiseco/Eagle, JWT S1 cams, BC valve springs, PT5857, ID1700 injectors, SR20DET ECU w/ Nismotronic, COP conversion with LS ignition coils, etc, etc...
--> YouTube channel --> my build thread
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drifting1two40
Driving Mom's Station Wagon
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Joined: Mon Jun 04, 2012 12:58 pm
Location: funkytown, tx

Re: after catch can install car smokes at idle and 1st gear

Post by drifting1two40 »

sorry haven't been on in a while.

my catch can does not have a filter or breather on it.
it only has two ports located on the top of it

I have left the catch can un hooked so to not cause any trouble

still interested in others setups to compare
thanks for the responses peeps
adamky
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Re: after catch can install car smokes at idle and 1st gear

Post by adamky »

So, if you had the valve cover breather going to one port, and the PCV valve going to the other port, you have essentially sealed off the only two places that blow-by has to escape the crankcase. You need to either set it up differently, or use a catch can with a 3rd hole so the blow by has somewhere to go.
Wiseco/Eagle, JWT S1 cams, BC valve springs, PT5857, ID1700 injectors, SR20DET ECU w/ Nismotronic, COP conversion with LS ignition coils, etc, etc...
--> YouTube channel --> my build thread
Image
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