check engine light code 402 fuel running rich
Country: United StatesMake: ChevroletModel: Blazer 4x2 (Full Size)Year: 2002
replaced ect sensor, valve covers and gasket, distributor cap
Are you sure the trouble code is P0402 I don't show that code?
no maybe 420 not sure but it has to do with the catalyct system also replaced oxygen sensor bank 1
For a p0420 you will need to replace the catalytic converter will need to be replaced.How have you tested for the engine running rich,usually there would be a code for rich fuel mixture.
I replaced the catalytic converter this time last year. how do you check for rich fuel mixture
You need a scan tool that reads data.You would look at the fuel trim data both long term and short term.This directly relates to fuel mixture.The fuel trim should be with +10 to -10 of zero.Excessive positive readings like -20 would indicate rich condition.Also any engine misfires would also damage the catalytic converter.
how do you correct rich conditions. what type of engine misfires?
A rich condition is usually a leaking fuel pressure regulator or leaking injectors.An engine misfire will usually be spark plugs and wires or fuel injectors.
The catalytic converter didn't solve my problem, the light came right back on! still stuck!
Have the codes been cleared and rechecked since catalytic converter replacement?If so what is the trouble?