Hello. New to the forum, but have owned my s70 since 05' (second owner.) I have done all maintenance on it, recently the timing belt serive, water pump, serpentine belt, plugs, etc. I've always got around pretty well, but I'm having some trouble with this one. I've taken the entire air intake (MAF, IAC, TB (XeMODeX Tech,) Hoses, Tubes, Etc.) and cleaned thoroughly. Don't worry, I only use MAF sensor cleaner for the MAF and connectors and etc. Now I'm getting the Bank 1 Code P0420 which says it's something with the catalytic converter system below threshold. I guess through more searching I found out it is something to do with the air idle valve. Can I take that apart? I have to go buy a special tip to remove the bolts because naturally the 100 tips I have currently do not help. I've cleaned it the best I can, but I can't get in there good enough. I keep having some rpm issues. Would that cause the vehicle to suddenly die at idle? Or as you are approaching a stop sign/stop light, right as you come to a complete stop, the rpm's dip well below timing idle almost dying completely? Any help would be great! Thanks in advance!

 

I've seen some posts that suggests the 420 code points to the injectors. You can try some in the tank injector cleaner (fuel detergent) or pull the injectors and use a shop that cleans them (typically this involves solvents and ultrasonic systems to clean out any gum) - expect something on the order of $10 per injector.

 

Ok, thanks so much! I will definitely look into that. Never would have related the two.