Dear All,
My 1990 Chevy G20 is running very rich (to the point of suffocation within 1 mile radius!!)
The engine is a 5.7L V8 TBI and I keep getting error code 44 (which according to my Haynes manual means "lean exhaust" measured by the Oxygen sensor mounted in the exhaust manifold. Clearly, it's not running lean and my first thought would be a faulty O2 sensor as I think the ECU is running the engine with a rich mixture to overcompensate. However, before I replace it, does anyone have any ideas (apart from a faulty ECU) what might cause this to happen? Is there a way I can test whether the O2 sensor is operating properly and sending back the right information?
(I'm in the UK so sourcing parts is not as easy or cheap as in the USA!! I'd rather investigate and order the right bit first time!!)
Cheers
Chris