2004 Discovery 2. Replaced up and down O2s. Replaced MAF with Bosch MAF. Replaced Cat Y pipe. Replaced Throttle Body gasket.
I am getting a P1174 and P1171 after a drive on the highway. I saw that on deceleration my Upstreams Drop to 0v and my short term fuel trim goes to +20%. This only happens on deceleration from high speeds. I have not done a smoke test for vacuum leaks. I suspect that it is upper intake or fuel injector O-ring. Pics of readings below.
I am getting a P1174 and P1171 after a drive on the highway. I saw that on deceleration my Upstreams Drop to 0v and my short term fuel trim goes to +20%. This only happens on deceleration from high speeds. I have not done a smoke test for vacuum leaks. I suspect that it is upper intake or fuel injector O-ring. Pics of readings below.