BPV was: CEL possible O2 sensor 1.6 bar now 1.3 SOLVED?

[David]

> Interesting sidebar for 20V'ers
> The Bosch bypass valve 710N:  Leaks air past it around 7-8 psi when new.
> Replacement I had put in 7,000 miles ago was clean inside and leaked at 8 PSI.
> The old one I replaced last year (kept as spare) leaked at 4 PSI
> 
> Chester  provided the pressure tester and Art from Salisbury Motor cars in NY 
> had a new BPV to lend for the test.  Phil watched too.
> 
> Thanks for the help.
> -Scott by BOSTON


One word...Forge. Bosch has had BPV/DV problems sicne that design came out back in the 80s. They've come out with a couple dozen varients and all leak at high boost and will eventually leak at lower boost levels. If you have or need a BPV, consider ditching the "known bad" Bosch diaphram type valve and get a decent aftermarket piston type. I replaced the Bosh on my 98 Passat with a Forge 006 (the larger of the 2 designs) when I chipped it (full 1 bar boost). Worked great for the 40,000 miles I had it after chipping, and I understand the new owner has had no problems and is now at over 120,000 miles (80,000 chipped miles).


Dave

1987 Coupe GT Special Build 2.3 
All in SE VA