Codes

Southern80 · Post by **Southern80** » 18 Apr 2010, 19:11

Good evening you all!!
I have a 1995 850 GLT non turbo and I am getting this codes from the A2 slot:
code 425
code 436

Also after a complete PCV cleaning I am still getting smoke coming from the oil dipstick. This after car got an oil change for multi-syntethic oil at Volvo dealer and car was seated for almost 2 months during cold weather.

Any help ?

Thank you

Brazuca_ny · Post by **Brazuca_ny** » 18 Apr 2010, 20:21

hi there as far as the smoke it could be moisture build up from the 2 months of siting w/out moving take it for a nice drive 10 miles + it should go away, I'm not familiar with the codes I'm sure the experts will help you soon

Post by **jblackburn** » 18 Apr 2010, 21:30

Both of your codes point fingers at the rear oxygen sensor.

425 - Rear o2 Signal missing/faulty
436 - rear o2 sensor compensation

Since you don't have any codes showing up for the front o2 sensor, I'd say it's fair game your rear one has just bitten the bullet.

Some people continue to have problems with the PCV system even after cleaning the whole thing. I think the problem traces back to excess pressure past the piston rings/valve seals that the system isn't designed to handle.

https://www.matthewsvolvosite.com/forums ... =1&t=28415

https://www.matthewsvolvosite.com/forums ... =1&t=27982

Southern80 · Post by **Southern80** » 20 Apr 2010, 20:05

Does the 1995 Volvo 850 GLT Non-turbo has PTC valve? If yes where is it located?
Thanks

Post by **jblackburn** » 20 Apr 2010, 20:29

There is no PTC on a non-turbo car. There IS however, a flame trap tube that comes into the side of the throttle body. There is a small plastic "filter" of sorts that clogs up and causes the PCV system to clog up. Take it out and throw it away if you haven't already, and you'll reduce the pressure.