Last week I washed my car and right after I gave it a wash the check engine light came on. An the anti slip light came on as well. I assumed this was caused by getting something wet during the wash. The next day both lights were still on. I unplugged the battery to clear the errors. A week later both lights have come on again. I'm going to bring it to the parts store to get the codes read next week. In the meantime anything I should look at that might be causing this?

Also to muddy the water more around the same time the car started to make a light knocking sound when starting but soon goes away when warmed up...kind like the sound of hitting two wooden spoons together. I don't know if I'm imaginging it but I'm thinking that I'm smelling a stronger than usual exhaust smell when starting....any thoughts?

Its a 2012 Fit Sport with 74k miles.

 

Your stability control turns off when you have a check engine code. Have any parts place check and read codes. They do it for free. There's no telling what you did or didn't do, could be coincidental for all we know.

 

I agree. When I had a loose spark plug, Check-Engine-Light (CEL) came on and the Vehicle-Stability-Assist (VSA) light also came on meaning it was disabled ('11 Sport AT), so the VSA condition is 'linked' to the CEL condition. Get the code read and if it's a misfire then highly likely a plug is loose and it was a coincidence that the CEL came on after the car wash and isn't the true cause.

Other's have addressed a loose spark plug by replacing all four (4) plugs and coil packs. That seems drastic and a costly solution when a single plug needs tightened and everything is still in good working order and probably would be years / miles into the future.