Stuck lean and rich codes

Has anybody had this issue? We have had it for a month and we did a tuneup and it still has the codes for stuck lean and rich on bank 1 sensor 2. Replaced both 02 sensors for the heck of it, new plugs and coils. I don’t see any damage to wiring.

Please post the exact codes

For example P0171 or P0172

I’m having a hard time picturing an oxygen sensor stuck rich AND lean at the same time

Bank 1 sensor 2 sounds like the downstream sensor . . . the one that monitors the catalytic converter efficiency. And as far as I know, there are no codes for the downstream sensor being stuck lean and/or rich, because the signal is not supposed to be rapidly fluctuating on that particular sensor

Are you saying you replaced both the upstream sensor and the downstream sensor?

No offense, but I feel something was literally lost in translation here

I’m getting P2270 and P2271. I replaced both sensors just to try and fix the issue but that was a waste. My code reader could be faulty or a ground issue. I’ll stop by autozone for a free scan soon.

hmm … that’s a new one, you got both a lean and a rich problem at the same time it appears. I’m presuming this is a 4 cylinder engine, right? So you only got one exhaust bank, bank 1.

I expect you already know it’s not possible for the engine exhaust to be lean and rich at the same time. So it must be too lean some of the time, and too rich other times. Codes for each instance are being stored. My guess, you got a fuel pressure problem. Sometimes it is too high, and sometimes it is too low. I’d probably start however by monitoring the fuel trims during various driving situations, provided have a scan tool that provides that sort of real time information.

Do you notice any other symptoms? Spark plug tips look black, covered w/soot? Smoke out the tailpipe? Stalling, hick-ups, lack of power during accelerations, overheating?

It seems to drive perfectly fine. Never overheats. Just had the valve adjustment done and they didn’t notice anything, said to come back when have more money cause with it showing both codes the dealer said it could be expensive to fix if it is the ECM. Yes 4 cylinder.

The problem w/waiting too long to address this is if it is really running rich or lean, the mixture problem could damage the cat. So you’d be saving money on delaying the diagnosis & repair, but paying it out again on the cat later. If you don’t notice any other symptoms, could well be just a wiring harness or corroded connector problem between the sensors and the ecm. What model year is your Element? Has it undergone extensive repairs in the past? Been in accidents? Flooded?

No accidents that we were told about. Had the fuel induction cleaning done, whatever it’s called lol. Also I just noticed that when you pull the o2 sensor out that is downstream connected to the middle of the cat, it looks blocked off, i cannot see into the converter due to it being filled with looks like carbon. Temp before cat is 326 and after temp at downstream sensor is 244. I measured temp at both sensors. Wife is taking it into the Honda dealer at 8:30 central today. Sweating bullets cause i need it to be a cheap repair but I feel like it could be the cat.

Results are in lol. Clogged cat. Someone had put the o2 sensor thing that you would use if you gutted the cat. Can’t remember the name. Putting new cat on today.

Are you getting the cat installed at the Honda dealer . . . that’s the most expensive way to go

Eastern Catalytic probably makes a good quality direct-fit cat . . . I can’t say for certain, because I don’t know what year your Element is, and what emissions standards it has (California or federal). But there’s probaby a handful of manufacturers. That name just came to mind

You might want to visit a few reputable exhaust shops and ask how much to install a direct-fit cat

How long are you planning on keeping the car?

Maybe that is a gadget that supposedly prevents the CEL from coming on if you have a marginal cat. In any event, glad you got the problem resolved OP. Happy motoring.