2000 S70 GLT SE no air pump relay installed, negative crankcase pressure

Henster · Post by **Henster** » 10 May 2018, 14:46

I have no air pump relay installed in my 2000 S70 turbo with 167,000 miles. There are no metal connector pieces for it in the relay box, but there is a space for it. Volvo.com couldn't give me a reason for it. I have been thinking about doing a PCV kit replacement as I have air pressure coming out of the engine oil refill, more at higher rpm's. Does anyone know if the air pump would cause this, or if this year model has a different relay for the crankcase ventilation. Otherwise, PCV/internal exhaust system cleaning or replacement (which doesn't seem to work half of the time, according to these forums). This project began because I had white smoke from the tailpipe only at startup, but no visible leakage anywhere at all. I found a loose clip on the air filter box, and the smoke hasn't come back, yet I have some air pressure from engine block still, not enough to burst a balloon. Any help or thoughts? Thanks.

Post by **scot850** » 10 May 2018, 16:14

Air pump to my knowledge was no longer used after the updates in 1999 models. If you had one it would be below the battery tray and unless someone had done a bypass for the system it would be throwing an engine code.

Air-pump only runs when a car is cold to reduced emissions. Once car is up to temp it no longer runs.

PCV/crankcase pressure is caused by a blocked or partially blocked system which sounds like the case in your car. Do you know when it was last cleaned? The 2000's V70's I have had have a large bore PCV pipe system which whilst not perfect tends to be better than the pre-99 version.

Only other causes would be valve giude seal wear or worst case worn/stuck pistons rings which is not common on a regularly driven car.

If the PCV system has never been cleaned it overdue.

Neil.

Henster · Post by **Henster** » 10 May 2018, 16:44

Thank you! Will look into it, maybe purchase my carfax report. Good to know about air pump, I suspected it never needed one. Guess I better roll up my sleeves and clean that mess...

Henster · Post by **Henster** » 16 May 2018, 16:46

Wow, after closer inspection, the hose leading to the PTC valve was completely unplugged! I recently had my timing belt done, water pump replaced, and master brake cylinder replaced. I guess my mechanic accidentally bumped the hose out of place, or it blew off from pressure. I will now clean the PTC valve, and then if needed, replace the PCV system. The rubber glove inflates a little, but when I rev the RPM's the glove gets sucked in. Very little dipstick smoke, and it runs like a jet engine again. Hallelujiah! Thanks for the help guys!

Post by **abscate** » 16 May 2018, 21:04

Just remember The PTC Is not a valve but a nipple or orfice.

Henster · Post by **Henster** » 17 May 2018, 08:00

Yes, thank you. I should edit that. I was a little excited lol.