PCV Problem on Boosted LT1
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Teching In
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PCV Problem on Boosted LT1 I have a 93 Trans Am 383 Procharged LT1 and it has a breather on the passenger side and driver's side valve covers and the PCV valve in the intake manifold is routed right next to a port to the right of the PCV valve on the intake manifold and I looked it up and I think that port is for the EGR valve. I bought it like this and I know its not the right way! So on the TB the bottom port was blocked off but the top port on the TB wasn't when I bought it! So I put my supercharger on and capped off that top port on the TB because you could feel air pushing out of the port and the next time I went to start it, it wouldn't start! It sounded like something was holding the motor back when trying to start it. I had fuel going to it and good spark and couldnt figure out the problem so I put new plugs in it and it started but ran like hell so I know something still wasnt right so I backtracked what I all messed with the car and I know it sounds weird but I took that cap off the top port on the TB and the thing started right up and ran good! But my boost gauge is reading 4 lbs of boost and on my other LT1 with the same supercharger I have on the car now it was running at 9-10 lbs of boost! Boost is leaking out of that top port on the TB but if you plug it off the car runs like crap! So im thinking its because that PCV valve on the intake manifold is not hooked up right and would like to know the proper way to hook it up because I think thats my problem!
Thanks, mxdirtking
Thanks, mxdirtking
You have a U shaped hose on the ds of the intake manifold. Make sure that's there as that's where the pcv is located on our 93's. Both ports on the TB can be capped off as that's how mine is. You've got issues somewhere else on that engine but where I'm not sure.
Yep, not sure what's up w/ your U-shaped hose but that's not a factory hose. Looks like the previous owner lost it or something. Shouldn't be that big and looks like there may be some restriction in it the way it's bent. I'm running breathers on both VC to vented catch cans and a oil water seperator inline w/ my pcv back to the intake. No problems whatsoever. Give me a few minutes and I'll get some pics up for you to see exactly how it's set up.
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Here you go.
TB ports capped off.
Top port ps side is boost ref for my fp guage. 2nd port is capped.
PS vc breather to catch can
PCV I'm using a different kind but you see it on the steel braided line going to my oil water seperator in the next pic. The nipple port next to it is my line to my boost gauge.
Lines going to and from the watts oil water seperator and the other breather to catch can.
TB ports capped off.
Top port ps side is boost ref for my fp guage. 2nd port is capped.
PS vc breather to catch can
PCV I'm using a different kind but you see it on the steel braided line going to my oil water seperator in the next pic. The nipple port next to it is my line to my boost gauge.
Lines going to and from the watts oil water seperator and the other breather to catch can.
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Verdad Gallardo Yes, but I'd try and find a factoy hose if possible. In your case in what you've described it sounds like you've got a crank case issue. You may just be able to just get the car running w/ that port capped off and see if the pcm will relearn the idle parameters. Not really sure it'll work but it won't hurt nothing either. Does he have any lines running off the procharger inlet to the intake anywhere? D1sc or P1sc not that that matters.
So did the car run strong prior to buying it? Sounds like maybe a spike happened and that caused that cap to blow off and somehow the car just adjusted to have the boost leak. Just throwing spaghetti on the wall at this point.
So did the car run strong prior to buying it? Sounds like maybe a spike happened and that caused that cap to blow off and somehow the car just adjusted to have the boost leak. Just throwing spaghetti on the wall at this point.
Launching!
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From: Weatherford Tx 76085 corner of N. Hwy 51 and 150 Green branch Rd.
Does it have an aftermarket throttle body? If so make sure they have a drilled out hole for the IAC sensor. I'm not sure if you said you were able to start it once you had the tb port plugged up.
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I will try to find a different hose. I bought it with just the 383 and it needed to be dyno tuned and ran pretty rich and then I put the p600b charger on it and it would run fine and everything it was just rich because it needed a dyno tune but that was when that pulg was uncapped I never really noticed it until we trailered it to get dyno tuned and Ion notice it was unplugged and he was doing part throttle tune just driving it around and get a lot of the bugs worked out and then when he got back he said that 3rd gear was slipping and we couldnt get it on the dyno to do the full throttle tune. But we got an all new built tranny in it now and runs good and this spring we'll be going back down to Ion to get the full throttle dialed in. Its just I noticed that it was only making 4lbs of boost with this car and on my other one I was making 9-10lbs and it is the exact same setup because to just took that charger and setup and swapped it over to this car that I have now and thats when I plugged that cap because I noticed that you can feel air pushing out that port when its running and the boost too. And thats when I plugged it and everything started acting weird.
Thread Starter
Teching In
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Yes it has a Holly TB on it. And I have tried starting it with it plugged and it just wont start. When its plugged and your trying to start it, it will try to pop off but it cant like something is holding it back and then you take the cap off and it fires right up.
Launching!
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From: Weatherford Tx 76085 corner of N. Hwy 51 and 150 Green branch Rd.
have you tried to take the throttle body off and check to see if maybe the gasket is messed up for some reason? I would try taking the blower piping off and run it (idle) N/A and then check to see if that port has vacuum. Every Lt1 that I've worked on doesn't pull any kind of vacuum (idle) through that particular port. I'm not to sure what could be causing that symptom but I would check the little things like that first. But I doubt it would cause it to be running that crappy.
