This answer is applicable for several BMWs additionally to the one listed below.
car year: 1997
car model: 328is
My BMW has failing emission check and that i have two codes. are you able to tell ME what those codes mean and also the half to repair it? P1423 and P1421.
These 2 codes area unit for the Secondary Air System, bank-1 and bank-2. Bank one is cylinders one through three and bank-2 is cylinders four through vi. These codes area unit indicating that the secondary air system isn’t functioning properly.
The secondary air system pumps contemporary air into the exhaust ports throughout cold engine start-up. This provides contemporary chemical element to help within the complete burning of the combustion mixture throughout the cold start-up amount, once the mixture is richer and isn’t burning expeditiously.
Commonly, the check valve at the manifold can fail (stick open) and this can permit exhaust gasses to enter the pump once it’s not running. this can destroy the pump. the standard repair involves substitution the pump and also the check valve (and the seal for the check valve). Of course, there area unit alternative areas inside the secondary air system that might be guilty. For additional data and elaborate diagnostic steps, please see the Summer 2008 issue of our quick Times account (below).
I have a 1999 BMW 323i and also the scan code unbroken developing p1188/1189 and p0170 and p0173 . What area unit these codes and the way do I correct the the problem?
The P1188 and P1189 codes area unit for “fuel control” for each banks one and a pair of (cylinders 1-2 and 4-6, respectively). The P0170 Associate in Nursing P0173 area unit for “fuel trim”, again, for each banks one and a pair of.
With these codes, i might 1st search for vacuum leaks within the intake system. examine the rubber boots going from the MAF (Mass Air Flow sensor) to the throttle body, particularly the little leg that connects to the idle management valve, down by the throttle body. in addition, examine all vacuum and air handling hoses. Another common vacuum leak supply is that the housing ventilation. See the link below for extra data on the housing ventilation.
If you can’t realize any obvious vacuum leaks, you’ll have the system “smoke tested”. This injects a smoke into the intake and any leaks can permit the smoke to return out.