I replaced the timing chain guide on a 2004 Maxima.
Car started on the crank and ran well up to 6000 rpm and 80+ mph.
Next day it started running poorly and blasting out greyish smoke.
Read DTC’s, P0171 and P0300. Found damaged the electrical connector on bank 1 variable valve timing solenoid. Fixed it and car ran well for couple days. Then started running very poorly.
No DTC’s. Found bank 2 catalytic converter had disintegrated probably due to running too rich, and had plugged up rear converter. Replaced it and cleaned the rear converter. The car started immediately and ran fine for a day then started blasting out white/grey smoke from bank 2 only and bank 2 only is running rich. Bank 1 fuel trims are fine and no smoke. The bank 2 pre converter O2 sensor is ok. Once again, there are DTC’s.
I removed the exhaust and the bank 2 converter is ok. O2 sensors are functioning and I also tested Ohms and they read ok but I went ahead and replaced the pre-converter sensor anyway. Checked camshaft position sensor and it was ok but went ahead and replaced it.
Checked for exhaust and intake leaks and found none but went ahead and redid the exhaust and intake plenum.
Checked fuel pressure and it’s ok at 43 psi. Verified the injectors on both banks aren’t leaking and tested with a pulse tester and they all are putting out the same amount.
Verified with stethoscope that bank 2 injectors are opening and closing. I didn’t think of this until after I put the plenum back on so I didn’t confirm bank 1.
Bank 1 short term trim is +6 to +10 at idle and +7 to -5 at 2500 rpm. Bank 2 is +12 to +14 at idle and -25 at 2500 rpm.
I tried to take off the bank 1 catalytic converter but gave up. I also couldn’t get the pre-converter O2 sensor out of bank 1 and wasn’t able to test it nor back pressure to see if it is plugged. I did remove exhaust pipes and the pressure exiting each converter felt the same.
I’m afraid to run it since running rich probably destroyed the converter the first time.
What else will cause one bank 1 to run OK and bank 2 to run very rich?
One bank running rich
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AZhitman
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Re: One bank running rich
OK, there's a head-scratcher. Let me get some of our more adept minds in here. Hold tight!
p.s. Great job on the systematic diagnostics thus far.
p.s. Great job on the systematic diagnostics thus far.
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NutriaforBreakfast
- Posts: 1316
- Joined: Wed Sep 26, 2007 1:41 pm
- Car: Nissan Maxima 1995 VQDE engine
Re: One bamk running rich
stuck egr valve?
Re: One bank running rich
humm, i posted and no one answered, but this is like my problem
ok, i have a 2004 murano 3.5, bought it use, had a few, well a lot of problems, so, changed both valve covers and pcv, plug oil seals where leaking, had one bad coil, got a set of new coils and plugs, original ones, used to have a code p0300, now its sometimes pending, once we replaced all those parts, it was fine for the first ride, after that, i get misfire or hesitation under light load or coasting, way to much gaz, not a real electrical misfire, idle or full throtle, no problem, things we founds, intake was full of oil, its smoking a bit, cat are empty, compression is betwen 130 and 138 all cylinders, we checked timing, cams are fine, the chain didnt jump, fuel pressure is 42 and higher on rev's, got the factory manual, its perfect, injecter where cleaned and tested, there all spraying fine and none are leakings, we had a 02 sensors bad that we changed, did the re-learn procedure, now, on o2 sensors, the readings are fine, on a/f sensors, bank 1 short trim ( long trims confirms it both) average is around 0% on driving normaly, but, on bank 2, average is a wopping 25%, but no code on a/f malfunction, just a pending 0300 sometimes when we try to drive it nicely, gas consumption is......like a v16 (drive computer says 32 ), we tested with propane for vacum leaks, none, all the vacum lines seems at the rigth places, im really getting desesperate, have an obdb car doctor for readings
so this might ne a stuck egr valve ? cause i aint got no code, so im assuming ether the a/f is lying or something else is causing it ? NutriaforBreakfeast, enlighten me
ok, i have a 2004 murano 3.5, bought it use, had a few, well a lot of problems, so, changed both valve covers and pcv, plug oil seals where leaking, had one bad coil, got a set of new coils and plugs, original ones, used to have a code p0300, now its sometimes pending, once we replaced all those parts, it was fine for the first ride, after that, i get misfire or hesitation under light load or coasting, way to much gaz, not a real electrical misfire, idle or full throtle, no problem, things we founds, intake was full of oil, its smoking a bit, cat are empty, compression is betwen 130 and 138 all cylinders, we checked timing, cams are fine, the chain didnt jump, fuel pressure is 42 and higher on rev's, got the factory manual, its perfect, injecter where cleaned and tested, there all spraying fine and none are leakings, we had a 02 sensors bad that we changed, did the re-learn procedure, now, on o2 sensors, the readings are fine, on a/f sensors, bank 1 short trim ( long trims confirms it both) average is around 0% on driving normaly, but, on bank 2, average is a wopping 25%, but no code on a/f malfunction, just a pending 0300 sometimes when we try to drive it nicely, gas consumption is......like a v16 (drive computer says 32 ), we tested with propane for vacum leaks, none, all the vacum lines seems at the rigth places, im really getting desesperate, have an obdb car doctor for readings
so this might ne a stuck egr valve ? cause i aint got no code, so im assuming ether the a/f is lying or something else is causing it ? NutriaforBreakfeast, enlighten me