Hi all, I've been reading and following along for some time but registered recently and haven't posted much. I have acquired a 2000 V70 XC not too long ago and want to stay ahead on the maintenance. As I've read on this forum, the PCV system may be the problem when it comes to oil leaks and I have an oil leak on the back of the engine that I've not been able to pinpoint (turbo return line gaskets have been replaced). The car has ~110k miles, so I decided to check out the PCV system just to be certain and have peace of mind. I found the tips and insight on this site to be very helpful, thanks to all, and thought I had done everything right. It wasn't too bad actually, there was one small hose that was completely clogged up but other hoses only had very little sludge and the catch can/canister was surprisingly clean. However after putting it back together the car idles very rough. Some grey smoke, there are no mechanical noises (meaning metal on metal, knocking), but it sounds like it misfires and occasionally backfires as well. I had disconnected and cleaned the throttle body with throttle body cleaner when it was off the manifold. The battery was disconnected before I started on anything. Ran well before this, now idles really bad. Could I have damaged the throttle body by cleaning it? Please help, can't drive it like this.

Also, plugs and air filter are new, changed the oil right after cleaning the PCV. Any and all ideas are appreciated.

 

Make sure you do not have a vacuum leak around the injectors and where the intake bolts on.

With the car running spray around everything with carb cleaner and if the idle clears up then you found your leak.

 

Thanks Tech, I'll do that tomorrow and report back.

 

I just realized that I didn't report back. Thanks to Tech, the car is running smooth once again. I managed to crease the throttle body gasket and it didn't seal - replaced the gasket and all is well.

 

Glad all is well now.

 

I went through a similar issue for well over a year with my BMW. It had a very rough idle that I couldn't seem to get fixed. Before you spend a lot of money and time throwing parts at it such as plugs and wires and caps and rotors and O2 sensors and what ever else you are told it needs, seriously check out the rubber boot between the air filter and the mas airflow sensor and mas and the throttle body. After hundreds of dollars worth of parts I finally got around to replacing the rubber boot for $35 and that was the problem. The rubber begins to harden and get brittle and the seals are no longer secure.

As for your oil leak at the back of your engine, I had a slow leak at the main seal. This I had replaced while swapping out the tranny.

Good luck

Shawn