I'm in the process of running AutoRX through my car. the engine was pretty sludged up when I got it. But I'm cleaning it now. I've gone through the clean cycle and early on the CEL came on. Now, I'm in rinse. The CEL is still on, but I was wondering how long it would take before things cleared out.
I'm planning on running another clean cycle in the car after this rinse. I'm a 1000 miles into the rinse and I can see plenty of sludge through the oil fill hole.
Are these typical codes to get when cleaning/rinsing? This is on a '99 Miata.
a miata forum search of posts with P0106 or P0420 in the title yields the below links (sorry but you have to register with the miata forum to view these)
.. so those appear to be common codes for the '98-'05 miata. As is sludge in general.
Ever notice how on a cold morning when you can see some car's exhaust, how it pulsates out of the tailpipe? That is, it does not stream smoothly, it looks more like individual puffs of smoke coming out the tailpipe, several puffs per second. Those puffs have a certain oxygen content, and then the clear air between the puffs has a different level of oxygen. Your oxygen sensor measures those differences, and when they fall out of spec, you get a code p0420. But that measurement can fall out of spec in a bunch of different ways - the catalytic converter may be bad, the sensor itself may be bad, your exhaust may be dirtier than usual due to a very dirty engine - which is what is hopefully the case with you. Throughout your cleaning and rinsing phase, your engine is actually dirtier than normal, because sludge that used to be stuck to the engine is now floating in the oil and can affect sensors and exhaust and sounds. If the codes do not go away by say, 1000 miles after your final rinse phase, then you might study up on the above posts. But there is no need to take action just yet. To clear the codes to see if they come back, you can disconnect the battery for 30 seconds to clear the codes, or go to an auto parts store where they will clear them for you for free.
P0106 is a boost sensor code but one guy on the forum got P0106 because he had a bad PCV valve. Its a $5 part and is a very important maintenance item in sludged engines - so you might get a new PCV valve if you have not done so recently. P0106 It can also happen with plugged or cracked vacuum lines, as in this guy's post
