PCV Routing Question

5L5SpdHardtop · Apr 19, 2009

Hello, I'm new to the forum. I've seen some good tech advice during my browsing so I thought I might be able to find an answer to my PCV system question. I bought my 95 GT some time ago. The more I get into the car, the more I see that the previous owner had no business attempting repairs. I have been slowly repairing any problems I find, many created by the previous owner. The problem I'm having is a terrible squealing noise very similar to a slipping serpentine belt. The noise only occurs when the engine is warm and under high vacuum, such as at idle or light throttle. If I shut the car off while it's making the sound, the squealing subsides very slowly as though pressure is bleeding off somewhere(the belt has stopped spinning a good 3-4 seconds before the sound stops). I have noticed that the crankcase builds excessive pressure, which led me to believe I might have a problem with the PCV system, thus leading me to my main question. My PCV hose currently exits the top of the PCV valve and travels a short distance to a "T" fitting, which then has one line that branches off and connects to a fitting on the underside of the upper intake, and one line that goes to a 90degree fitting on the end of the upper intake closest to the brake booster. The "T" doesn't seem necessary to me and I have no other cars in the area to look at for reference, so I can't be sure this isn't more of the previous owner's molestation of the car. I have a new PCV valve and filter for it, but I'm not sure if the routing is correct. Currently, my only other suspect for this problem is the hacked up air injection system that's on the car. If anyone has any input for my problem, it would be much appreciated.

94 DropTop · Apr 19, 2009

You might ust need to replace the vavle and the mesh screen in the lower intake. Do you have a seond hose that runs from your filler tube on the valve cover to the intake. If thats not there it might build to much pressure also.

95 svt cobra · Apr 19, 2009

+1 your PCV probably needs to be replaced. That routing is correct with the T fitting going to the brake booster on a stock intake.

5L5SpdHardtop · Apr 20, 2009

Thanks for the replies, I fixed the problem. I have the PCV parts and still intend on replacing them, but 94 DropTop gave me the info I needed...I checked the breather hose that goes from the oil fill neck to the intake tube and found that it was plugged solid. I've never seen one plugged before, so I popped off the intake tube between the airbox and the throttle body. I found that for whatever reason, the previous owner thought it would be a good idea to put mass amounts of glue inside the intake tube(cracked or broken maybe?). The glue was all the way up into the breather tube. I found a replacement on ebay that I hope shows up soon, but in the mean time, I just used a drill and cleaned out the plugged holes.

94 DropTop · Apr 20, 2009

He probibly did it cuz it will put a lil bit of oil in the intake. I put a breather filter where my oil cap went and capped the openings. and mine is fine on pressure