Subject: Try this also--charcoal canister breather valve Author: cheung1 as Patrick C 88 750 160K : member since March, 2004 : 843 posts Posted on: 2008-06-09 17:12:41

Here is something I had tried along the rough road of battling bad oil consumption and smoky exhaust (until I replaced the piston rings). Open the hood and you can see a pair of rubber hoses going into the neck of each of the two DKs. The thinner of the two hoses comes from the charcoal canister breather valve, which is mounted next to the air filter plastic housing by an oddly positioned small bolt.

The breather valves are electronic controlled (solenoid) to open up and allow the intake to suck in some fuel vapor collected in the canister from the gasoline tank. The breather system bypasses the MAF so the engine has no idea how much air or fuel has entered from the breather. If the valve malfunctions, or if the charcoal gets old and soggy a wrong dose of fuel can be sucked into the intake and upset the air/fuel mixture badly.

Here is what you can try: block the thinner hose with a hose pincher or friction tape, etc just so the breather system is isolated from the intake vacuums. Do this temporarily and see if the smoky problem improves. Any improvement can be seen immediately. Undo the change shortly so the gasoline vapor has somewhere to be burned off.

Patrick C 88 750 159K

• Need help from a fellow 750 owner.......my car's fuel mixture - eliasazem 2008-06-09 16:20:37 (67 views)
  • 2.4 litres an hour (nt) - alv12 2008-06-09 20:43:41 (40 views)
    • Did you get this reding with the engine cold or warmed up? (nt) - eliasazem 2008-06-09 21:15:31 (38 views)
      • warm it goes from2.3-2.4 I will try it when cold and let you - alv12 2008-06-12 23:34:25 (28 views)
  • Try this also--charcoal canister breather valve - Patrick C 88 750 160K 2008-06-09 17:12:41 (67 views)
    • Just found out that PO removed the whole system :( (nt) - eliasazem 2008-07-02 14:09:13 (18 views)
    • I'll also give it a try...thanks Patrick (nt) - eliasazem 2008-06-09 19:40:55 (37 views)
  • that is liter per hour consumption - shogun 2008-06-09 16:55:30 (59 views)
    • I mean to adjust my idle consumption.....maybe I can get - eliasazem 2008-06-09 19:35:25 (35 views)
      • multimeter, read the values by measuring (url) - shogun 2008-06-09 23:54:25 (52 views)
        • details what you should get as data (url) - shogun 2008-06-10 00:10:28 (45 views)
          • Did a auto data scanning today and foud out that I had a bad water temp sensor - eliasazem 2008-06-11 20:06:42 (52 views)
            • yes, there are more than 2 coolant sensors (url) - shogun 2008-06-12 19:29:36 (45 views)