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I havent found out the issue yet. most people on here suspect the 02 sensor being faulty but it was swapped and same results. the thing is 02 sensors shouldnt be used at cold startup . the car is rough and spits for about 5 seconds at startup and stays rough hot or cold. im suspecting timing must of been slightly off.
I'm new here and just started reading this thread...after 4 pages I feel too invested in it now to not respond LOL
So to summarize:
1. Runs like crap even in open loop (no O2 input). Rules out the O2 sensor.
2. Can't be common vacuum leaks or EVAP or EGR stuck open or MAF or ECT sensor etc otherwise it won't be lean on just one bank.
Question
Spraying brake-clean makes the O2 rich but does it run any better with the additional fuel? Injectors not delivering fuel properly is the biggest suspect to me.
spraying brake clean makes it rich but does not make it run any better. im thinking the timing is slightly off on one head. it has two chains that run the timing. it makes no other sense everything seemed to tested ok. popping from the intake seems kinda odd as well.
I agree that if it doesn't run better with the additional fuel then it's likely not an injector issue either. You make a good point about the timing being off on one bank.
its possible the valves are closing when the injector is spraying showing the lean issue due to the timing being off. I will update everyone watching this post on what I see.
Then the snap on has you probing the wrong wires, because that is an ignition wave form, and it's not a great one. It looks good sometimes, and other times it's sloped down instead of up with no kick at the end. That's a plug misfire. And sometimes it's not firing at all. If you have a misfire you will have fuel trims going lean from the unburnt fuel once it gets into closed loop. I think you're chasing down the wrong hole with the O2 sensor. It's a problem, but not the problem. Check your plugs and wires again, but I suspect you may have a weak coil. Pull the wires off one by on and do Pauls favorite test light spark gap test to see if you are getting a nice long spark off of each one.
disable the fuel pump then crank the engine for several seconds. If it cranks even, you have no timing problems.
The lean condition is causing the popping.
Have you checked the EGR. Just to rule it out... make sure its closed. EGR problems are global not bank specific, again just to rule it out.
When did this problem start? was it sudden or after some repairs
got to ask, but you are swapping the 02's upstream to upstream not upstream to downstream.
the error codes are related to voltage. the heater side of the 02's are ground controlled by the pcm and each 02 has its own ground at the pcm. check the ground wire of B1S1 by unplugging the pcm and the 02 then using your DVOM in Ohm mode connect to each end of the ground wire and check for continuity. If I'm correct the wire is brown, either solid brown or a brown with another color stripe.
"an open mind let's knowledge flow in and wisdom flow out for a man who has neither never listens to those who have both".
Being wrong doesn't bother me, it's being right and not understanding why that does
I cleaned out the egr it was closed when I checked it. injectors were flushed out and swapped around. what I notice was sometimes during cranking it cranks normal and some times it bogs down for a few seconds as if battery is weak. it has a new starter on it so it cant be a starter.
swapping the correct up to up and down to down. the issue started out of nowhere. there is a clanking sound as if the chain is hitting something. so im thinking timing. the injectors are firing its like when they fire into the cylinder the valve must be closed during that event, maybe causing the lean issue.
the slow cranking can be something to look at... excess fuel in a cylinder can cause this that's why you disable the fuel pump (pull the fuel pump relay) when doing that test.
Have you done a compression check. A leaking head gasket can cause the slow cranking due to cylinder compression in an adjacent cylinder leaking past the head gasket. This would be a bank specific problem. It will cause a rough idle. Just how rough depends on the amount of leakage from the head gasket.
The clanking sound can come from a loose timing chain. The tensioner gets worn and the chain becomes loose and can slip a tooth or two. It can also come from compression leakage from cylinder to cylinder causing chain lash as the engine stutters.
Eliminate those two... do a compression test and check the timing chain tension and position. I cant figure how those could cause a voltage code error, but eliminate them as a source of the problem.
I have to say that I've seen this same problem on a Mazda on this site, it was caused by a bad heater in an 02.
"an open mind let's knowledge flow in and wisdom flow out for a man who has neither never listens to those who have both".
Being wrong doesn't bother me, it's being right and not understanding why that does
You've got a lot of advice to work through, I would just like to point out that on this engine it is easy to connect the ignition coils to the wrong connector.
im still working on testing different things. vehicle ran good out of nowhere the issue occurred. the coils wasnt touched at that time until the issue for some testing. found some weak coils replaced them but no real improvement in roughness or performance
