95 850 Turbo. Tube from dipstick to ptc ok?

2012 · Post by **2012** » 19 Apr 2015, 21:20

Hey guys,
I found a way to relieve pressure from the crankcase due to clogging Pcv by running a tube from the dipstick tube to a vacant nipple on the ptc. Is this ok to do for a while? Anyone done this or something similar to relieve crankcase pressure? Thanks for your input...

Post by **erikv11** » 19 Apr 2015, 21:25

There are lots of ways to route such an overflow hose. The one you mentioned sounds fine except for one thing: there shouldn't be any vacant nipples on the PTC, this suggests a line is dangling open somewhere. I think I'd start by checking out and getting in place all of the vacuum lines. Then check for crankcase pressure and if you may want to vent it until you can fix the PCV.

Post by **kahl** » 19 Apr 2015, 21:36

He may mean the vacuum tree on top of the throttle body?

Post by **atucker1** » 19 Apr 2015, 22:30

Just to back up Erik, double check the little hose on the PTC. If it is clogged or disconnected, the entire system will cease to function.

2012 · Post by **2012** » 19 Apr 2015, 23:18

erikv11 wrote:There are lots of ways to route such an overflow hose. The one you mentioned sounds fine except for one thing: there shouldn't be any vacant nipples on the PTC, this suggests a line is dangling open somewhere. I think I'd start by checking out and getting in place all of the vacuum lines. Then check for crankcase pressure and if you may want to vent it until you can fix the PCV.

I attached my hose to the nipple just to the right of the connector on the PTC, down by the turbo. Its actually on the intake duct, just to the right of the PTC, a little larger than the other vacuum lines. This nipple had a cap on it that looked old and brittle, like it was blocked off for quite a while. Which tube is actually supposed to connect here? Maybe this is why I had blowby?

Post by **erikv11** » 20 Apr 2015, 01:29

That nipple is supposed to have a line that runs up to a couple check valves and the EVAP solenoid and then connects to the vacuum tree. It is line number 6 in this post (https://www.matthewsvolvosite.com/forums ... hp?t=63615) and you can also look at the vacuum hose diagrams there.

The EVAP line is probably not the cause of blowby on your car but if it is missing then who knows what else may be screwy, really you may want to check over all of the lines, note atucker1's comment: if one is disconnected or clogged it can indeed cause major blowby. You will want to do a full PCV service and clean out the ports to the block.