Leak into CC/PCV hookup

[Grescht]

ok, so i bought this car awhile back. I've done a few boost leak tests from the turbo inlet and air leaks into the CC. so i figure maybe turbo seals, or the car is cold and there is no oil pressure. still boosts fine though. anyway..... moved the BLT to the Licp. No leaks except through the oil cap. Ive done my fair share of searching and figured that my pcv hose isn't connected to anything. i've read that you have to hook it up into the intake but where. and obviously this was done for a purpose, because there is no leak in the intake mani anywhere. So what this forum is pointing to is valve seals. but it's a newly rebuilt motor with a 7-bolt head. soooooo. The reason i started the BLT's in the first place is because sometimes on warm starts it will stutter until i rev it up for a few. then it stops. and the other reason is that once i'm done running a little hard and i let the rpms drop back to idle, it will almost cut off and then pickup and stutter until i rev it. Any ideas? i'm going to do a compression test tonight. Thanks alot. and if i missed something on the search point me the right way.

 

[Grescht]

so. i ran the compression test and got 145, 147, 147. i didn't do the last one because i dropped a cap of oil into number 3 and oil blew out of the gasket between the manifold and the turbo. i ran tonight and ran a half second slower than last time. the car doesnt feel as fast either. no boost leaks as far as i know either. any ideas? yeah disregard those numbers. the car was at operating temps. whoops

 

[95CarbonEclipse]

Dude... have you checked your PCV valve to see if it's working properly. OEM PCV valves are notorious for going bad in less then 3k miles. The VC hose that leads to your intake should be connected, but it would not effect the results of a BLT since you shouldn't be boosting your CC. If you're PCV valve is bad, I wouldln't even worry about getting a new one, I'd just do the check valve mod. If you do decide to replace the PCV valve, you should still do the check valve mod, but don't waste your time and money buying a PCV valve from anywhere else except the Stealership (they at least work for a few thousand miles... usually).

A good way to check your PCV valve is to disconnect it from the VC and when doing a BLT, put your thumb over the PCV valve snorkel to see if it's allowing air to pass through. It should not allow air into your VC.

 

[Grescht]

i think the pcv is set up the way it is for a reason because my egr is blocked. but i still cant figure out why there is pressure leaking into the cc. could it be my timing being off a tooth on the intake side? well my car is running super rich and itll blow a puff of black smoke at wot. but onl a puff. any ideas?

 

[95CarbonEclipse]

i think the pcv is set up the way it is for a reason because my egr is blocked. but i still cant figure out why there is pressure leaking into the cc. could it be my timing being off a tooth on the intake side? well my car is running super rich and itll blow a puff of black smoke at wot. but onl a puff. any ideas?

I'm not saying that it's NOT set up the way it's supposed to be. What I'm wondering is if you're current PCV valve is faulty. A properly functioning PCV valve for our cars should allow air to move freely out of the VC, but should not let air enter the VC. If your PCV valve is faulty, then you could be pressurizing your CC, and that could possibly explain both the smoking issue and the leaking of air into your VC during your BLT.

 

[Grescht]

I've checked my Pcv valve and it is working properly. Air is venting out of the VC during the BLT. But thats where all my boost is leaking. The system will not hold a static pressure for any length of time. and this is a BLT from the LICP sooo..... it seems to me the only way boost could be leaking into the CC/VC is through the Valves. And thats what i've heard is Valve Seals.... but what are other symtoms of that? And back to the timing. could the intake valves be open slightly? Im under the impression they are stock Cams... because there isn't anything different about the car. and i think the previous owner would have said something. should i rotate my motor so any certain position during the BLT. and if i can find why it's leaking into the CC then i can start doing tests from the turbo inlet which i then will be able to see if my turbo seals are bad...... sooooo i'm in an odd place right now with a car that isn't as quick as it was due to Richness..... and when you rev it, you smell Gasoline. big time.

 

[Grescht]

just a thought.... could me running a 14b instead of the t-25 on the 6-bolt with the stock 97 computer have anything to do with me running rich?

 

[95CarbonEclipse]

ok, so i bought this car awhile back. I've done a few boost leak tests from the turbo inlet and air leaks into the CC. so i figure maybe turbo seals, or the car is cold and there is no oil pressure. still boosts fine though. anyway..... moved the BLT to the Licp. No leaks except through the oil cap. Ive done my fair share of searching and figured that my pcv hose isn't connected to anything. i've read that you have to hook it up into the intake but where.

Just wanted to answer this question that you had. I've attached a couple pics of exactly how the PCV hoses should be hooked up and to where. Hope this helps. Also, having the EGR blocked off or removed does not effect the PCV hoses. There is another hose that connects from the Intake Pipe to the Charcoal Canister that is EVAP related, but if your EGR is "blocked off" and not completely removed (along with the rest of the emissions equipment) then this hose should still be connected.

You can see that the red hose goes from the VC to the Intake pipe in the attached photo (indicated by green circles) and the hose connected to the PCV valve goes to the intake manifold (indicated by the red circles).

 

[Akoi Meexx]

Just wanted to answer this question that you had. I've attached a couple pics of exactly how the PCV hoses should be hooked up and to where. Hope this helps. Also, having the EGR blocked off or removed does not effect the PCV hoses. There is another hose that connects from the Intake Pipe to the Charcoal Canister that is EVAP related, but if your EGR is "blocked off" and not completely removed (along with the rest of the emissions equipment) then this hose should still be connected.

You can see that the red hose goes from the VC to the Intake pipe in the attached photo (indicated by green circles) and the hose connected to the PCV valve goes to the intake manifold (indicated by the red circles).

Wow, got similar information for '90-'94 Talons? I'm almost sure I've got the hose in the wrong location now going from the valve cover... I'll take some pictures when I get out of work.

 

[95CarbonEclipse]

Wow, got similar information for '90-'94 Talons? I'm almost sure I've got the hose in the wrong location now going from the valve cover... I'll take some pictures when I get out of work.

I can't imagine it being that different then the 2g's. Basically for your PCV system to work properly, your CC needs to see vacuum both under boost and vacuum (idle). When under boost your IM is pushing air into all the ports and hoses that are connected to it. During this time the CC is being vacuumed via the VC port that is leading to the intake pipe (turbo spool is sucking in air through this hose). This is why it's so important to have a properly functioning PCV valve, as you don't want to be pressurizing your CC. Under idle/part throttle conditions, the PCV valve opens and the vacuum created in the IM is sucking air through the PCV valve.

Whether it be a 1g or a 2g set up. There needs to be one hose leading to your IM (with a PCV valve inline) and another hose leading to the "pre-turbo" side of your intake pipe. For more in depth information about how our PCV systems work, and the importance of keeping it functioning properly, check out the http://www.dsmtuners.com/forums/newbie-forum/229338-stupid-pcv-question.html thread.

 

[Grescht]

ok. so ill figure this thing out. ill mess with it tonight. is there any mods you can do mod wise to these cars that would eliminate the need for the pcv to be hooked up? and is there anything that could make it so you dont have to run the vent on the vc back to the Intake?

 

[95CarbonEclipse]

ok. so ill figure this thing out. ill mess with it tonight. is there any mods you can do mod wise to these cars that would eliminate the need for the pcv to be hooked up? and is there anything that could make it so you dont have to run the vent on the vc back to the Intake?

Why would you want to eliminate the PCV? It's there for a reason and it's to prolong the life of your engine. If you're worried that your PCV hose is allowing pressurized air to enter your VC, then you should try gettilng an inline check valve and installing it between your PCV valve and your IM. That is the only hose that, when boosting, will allow air to enter your VC and potentially escape from your oil cap.

If you're still convinced that your rings or valve seals are bad on a freshly built motor. Try doing a compression test, and then a leakdown test to see how bad (or good) your rings and seals are. This is the only way to really tell. A BLT is not an effective way of diagnosing anything other then boost leaks.

As for your problem concerning the rough idle and the drop in RPM's. What mods does this car have done to it? I've seen threads on here related to lightened flywheels that cause the same symptoms that you're describing. Also, check for bad ground wires (primarily around the battery), as a ungrounded alternator won't function properly and the only way to keep the engine running is to keep the R's up.

 

[Grescht]

i talked to the original owner of the car and he said the pcv hookup was a preference..... that the only thing it does is put oil back into your IM..... is there any reason there SHOULD be boost in my VC? if i re route the pcv hose and take the plug out that he put in the IM could this fix this?

 

[95CarbonEclipse]

i talked to the original owner of the car and he said the pcv hookup was a preference..... that the only thing it does is put oil back into your IM.....

I give up...

Ask the previous owner what to do. He seems to know more about these cars then I do.

 

[Grescht]

no no. dont take what i said the wrong way. to me his statement sounded wrong. i was bringing up the point to see if there was any truth to it. im just in this to try and make this car run better. and maybe get better than 20 mpg drivin like a grandma. driving the car normally now feels like something is pulling the rpms down if you push in the clutch in at 55mph. the car just isnt running good anymore. it feels super rich. im gonna do a blt on the pipes only. and then reconnect the pcv valve. just trying to bring ideas up.

 

[Grescht]

did a major leak test. from the turbo inlet to the throttle body it was lesking through the turbo seals... o i moved it to the licp. had two decent leaks. fixed them. hooked my pcv and vc vent hoses back up the correct way too. did another leak test and the only place air is leaking is into the vc. im guessing through the valve stem seals. it sounds like alot of air is moving in the IM. took it out and ran it. still runs like shit. if i rev it and let the rpm fall it will stumble nd recover still. but its still running super rich... i dont know what else to do. i dont want to take it to a shop but i think im going to have to. any ideas?

 

[ak47mopar]

Just wanted to answer this question that you had. I've attached a couple pics of exactly how the PCV hoses should be hooked up and to where. Hope this helps. Also, having the EGR blocked off or removed does not effect the PCV hoses. There is another hose that connects from the Intake Pipe to the Charcoal Canister that is EVAP related, but if your EGR is "blocked off" and not completely removed (along with the rest of the emissions equipment) then this hose should still be connected.

You can see that the red hose goes from the VC to the Intake pipe in the attached photo (indicated by green circles) and the hose connected to the PCV valve goes to the intake manifold (indicated by the red circles).

does the one hookin up to the intake pipe on the green circles have to be hooked up? my aftermarket intake pipe has nowhere for it.

 

[DSM nOOb]

holy thread revival. It should be hooked up. but does it have to no