0bd2 monitors not resetting

carbuff

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So, my 02 v6 vert will not pass emissions in NY. It passes the safety inspection part but will not pass emissions because some of the monitors are not ready. In no particular order the 02, o2heater, and catalyst will not reset. The evap will not reset either but Im allowed one not set to still pass. There are like 4 or 5 other monitors that have reset no problem. The live data for the o2 sensors as viewed in forscan look proper. My main question is since many of the monitors reset quite easily, I can repeat them resetting no problem, can I eliminate engine temp as an issue? I mean if that was an issue then the egr would not reset either right? The engine runs fine btw. NY will not let me renew the reg because it has not passed inspection in over a year, or I would not care.
 
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carbuff

carbuff

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Btw, Ive put about 2000 miles on the car over last summer trying to complete the drive cycle. No luck with that
 

shovel

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Have you fixed any of these issues and it won't reset? Or is it telling you to fix them.. I don't know if evap is the same on a 02 v6 as it is on a 96 v6 , but if it is the system is dead simple it's some hose and a valve and a sensor. The valves get stuck eventually, you know 20 or 25 years of eating a diet of goop will do that. So you replace the valve and the sensor and a few dollars worth of emissions tubing and the problem's solved. If the evap canister is in the same place, the hose always deteriorates closest to the canister inside the pass. fender.

Have you replaced the oxygen sensors? Those are sort of a wear part (well they don't wear exactly, but the membrane gets coated over time which might as well be the same thing) so I'd replace them at roughly 100k miles or just as routine maintenance, they're not particularly difficult or expensive if you DIY stuff.
 
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carbuff

carbuff

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I forgot to mention that I have no codes or pending codes. Just p1000 which is for monitors not ready. The whole problem arises because the battery died over the winter while in storage. so it reset everything in the computer making it so I need to complete the drive cycle to reset all the monitors before the smog machine will even look at the computer for state inspection purposes. If the o2 sensors were not working right or the heater circuit was broken would that trigger a pending code? I really have not tried much with the evap system because the procedure for getting that monitor ready is a bit tricky and NY state allows 1 monitor to be not ready for my year car. The 3 other monitors are all o2 sensor related so I figured its probably one problem causing all 3 not to reset.
 
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carbuff

carbuff

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Also isnt the o2 heater monitor supposed to reset right away while the car is idling in the driveway when you first start it from cold? Ive just learned of a fuse, fuse 8, that powers the o2 sensor heater circuit. I will have to check it to see if its blown.
 
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carbuff

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Well just in case anyone is following this, I have discovered a couple of things. So I had absolutely no codes. I pulled the fuse #8 that supposedly is for the 02 heater circuit along with a couple of other things. I drove the car around the block, turned it off, started it again and drove it a mile or so and I got a check engine light. Got home and checked it with the scanner. 7 codes. 1 for each of the heater circuits not heating (4 total) 0ne for egr solenoid, 1 for evap vent solenoid, 1 for purge control valve. So fuse 8 powers a few "engine controls". So I put the fuse back in cleared all the codes, which resets all the monitors too, and drove it around for a few miles. No check engine light. I checked for codes, none. I checked the monitors and they had all reset except for the same 4 that are stuck. So, this leads me to believe that the heaters in all my o2 sensors are working fine, or I would get a code. The wiring is all good too because that would set a code also. The computer is working properly. Also the other monitors reset easily so I dont think engine temp is an issue. I dont think the egr would set if there was an engine temp issue. Still has me stumped but at least I know a little more and for now see no need to unleash the parts cannon as it all seems to be working properly. Next Im gonna check my exhaust manifolds for cracks and leaks as I ve heard that can cause o2 problems. I know I have a tick that goes away after about 45 seconds in the morning when cold. And it is exhaust,not engine mechanical.
 

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