CR-V 1.6 I-DTEC went into "limp home" mode, has been in the garage for 5 weeks with no fix...error code was P1237 - Boost pressure lower than expected, other error code was P149E which AA couldn't locate. Garage & Honda Tech have so far failed to find a fix. Turbo may have been replaced & EGR also. Car is 18 months old with 10600 on the clock. How long should I give them before demanding a replacement?