P0443 engine code

[mellotron]

I have a '14 Rogue S AWD that is throwing a P0443 engine code. It first appeared last fall, but cleared on its own several weeks later when winter (ie, freezing) temps set in. It came back last March, when the temps warmed up, and of course now it won't pass inspection. No obvious symptoms other than the engine light (maybe a slight decrease in MPG, but that could be attributed to my daughter's been driving habits also )

I had a mechanic go over it and he replaced the purge control valve (and verified with a battery that the new one is functional), the vent valve, and he blew out the system in case there was any junk in the vac lines. Now we've run out of ideas. A meter across the wire harness shows that the wires aren't shorted together. When I turn the car on, the harness does have 14v at the valve, which I thought was high, but I haven't been able to verify what the voltage should be there (I thought 12v?). I've looked at the wiring harness and haven't been able to find any obvious frayed or broken wires. Unless I'm missing something, seeing voltage across the harness should indicate there isn't an open in the wires either.

The only other code that comes up is 0444 when I disconnect the wiring harness from the valve to check the incoming voltage. Plugging the harness back into the valve clears the 0444 code. I can clear the Current and Pending codes with an ODB2 connection, but the Permanent code never clears after driving it for a while. Eventually the Current and Pending are thrown again.

I've already had a mechanic suggest I wait until winter to get it inspected when the light goes out again but I'd rather make sure it's really fixed. Any ideas what am I missing that could cause an 0443?

[VStar650CL]

P0443 occurs when the ECM detects purge flow even though the Purge Volume Solenoid is completely closed. With a new Purge Solenoid, I'll assume it isn't leaking. The Evap Pressure Sensor can cause P0443 if it's malfunctioning, since that's what the ECM uses to detect purge flow. The sensor should read something very close to 4.0V with the tank vented manually to atmosphere and the Purge Volume Solenoid off (which it should always be at idle). The sensors don't fail often, but the orifice can get clogged and cause the sensor to hold a false reading. If the Evap is full it can also flood the sensor or its connector. If the sensor seems healthy, check to see if the Evap is flooded or the Vent Valve is physically clogged (there won't be an electrical issue with the Vent, since the ECM would throw a different code). If that all checks out, see if the ECM is driving the solenoid correctly. Back-probing the solenoid, there should be battery voltage at both terminals at idle. If you only have battery voltage on Yellow, then the Tan wire may be shorted to ground, the ECM driver may be melted to ground, or your new Purge Solenoid has an open coil. To find out which, disconnect the solenoid and the ECM and ohm the Tan wire to the block. It should read infinity or it's shorted. Then ohm the solenoid coil pin-to-pin, it should read something higher than 0 but less than infinity. If it does, then your ECM has a blown solenoid driver. If it's 0 or infinity then your new solenoid has a bad coil. If that's all normal, with the solenoid connector detached, you should see battery voltage on Yellow-only. If there's battery voltage on both when disconnected, then your harness is shorted to power (and probably the ECM is blown). The solenoid gets constant power on Yellow and the ECM drives it by grounding Tan, which is why you see battery voltage when the solenoid is off. Back-probing Tan, you should see a drop in voltage when the purge system activates. The best way to check it is with work support from a good scanner, but if your scanner won't do it, warm the car fully and raise the RPM to around 2500~3000. The voltage on Tan should begin to drop after about 30 seconds, indicating the ECM is trying to purge. If you don't get movement, then either the tan wire has a bad connection to the ECM or the ECM is bad. Hope this helps you!

[macgiver]

This is just a warning , of how really BAAAAD " offseas " parts can be .Consider the replacement part may be an "incapable imposter of an OEM part " . I'll explain .
In a nutshell , on daughters Hyundai ,2010 , Elantra 3 of those typical codes for ' purge solenoid " , and 'vent solenoid' ,and another ' vent ' code happened and Autozone Duralast part STILL had codes , RockAuto part STILL had codes , same as original " Bad " part .Were talking the " Purge Solenoid " , which is near the motor - up front. A man on youtube had miraculously found his problem solved , my problem solved , probly thousands of Hyundai cars .
It all came down to poorly produced contracted parts mfr. This guy on youtube found BOSCH to be superior & BOSCH DID NOT RETURN CODES !
But I went to Hyundai figuring , OK Hyundai ' Genuine ' GOTTA work right ?

The Hyundai parts guy hands me a Hyundai box , w/Hyundai part # , w/ plastic bag w/Hyundai part# too.
Guess what Darn Hyundai sold me ????????
A F 'n BOSCH PART.........BOSCH PART...............................................BOSCH !!!!!!!!!!!!!!!!!!
Supposedly , an explanation is that these PWM (pulse width modulated ) vent , purge , valves and many other "modern " computer controlled components DO NOT SIMPLY OPEN AND CLOSE . They , ya might say 'flutter' the pintles , PWM like , ALMOST like a fuel injector .
And these crappy 'overseas' mfr's CANNOT PUT THE SPECS PROPER in their parts , like they run on the 'fringe' or borderline , ready to F - UP BIGTIME .Purge Solenoid seems more finicky than her Vent Sol.

Bosch seems to be the best , especially for emission components , the Stealerships even evidently know this !!!
I'm now looking ONLY for BOSCH - BOSCH - BOSCH parts , especially emissions components

[VStar650CL]

Bosch seems to be the best , especially for emission components , the Stealerships even evidently know this !!!
I'm now looking ONLY for BOSCH - BOSCH - BOSCH parts , especially emissions components

I have to give that a big au contraire, I've seen people all but pull their hair out over Bosch A/F and HO2S sensors. IMHO Bosch ain't what they used to be, their standards have gone to crap ever since they stopped being a mostly-OE supplier and started selling retail products.

On the other subject, there's nothing very mysterious about any sort of solenoid, PWM-able or otherwise. The Far East tends to do well with them, and I've seen plenty of people do okay with wire-wound parts from China. Not that I'm particularly advising it -- China is still China -- but you're far less likely to have issues with a China solenoid or motor than with a China A/F or Hall sensor.

[macgiver]

Gotcha , it was just so lucky finding the youtube , and doing what the guy proved , finally Bosch working in her car when two other mfr's parts didn't .
The most amazing thing was how the Hyundai dealer themselves , , introduced the BOSCH part into their bag ,and in their parts box ,..............LOL

[macgiver]

VStar ......... sorry .......I'm embarrassed ........Did I use the term - " stealership " ? , can you ever forgive me ??? ....... First heard that from an AMC49 here Twas INSTANTAENEOUSLY FUNNY (at the time)
LOL.....................

[VStar650CL]

No offense taken. Some dealerships richly deserve it. This one for instance:

post6827800.html

Sounds like the one in your little diatribe may have deserved it too. I only get upset when people use terms like that with issues the dealerships can't do anything about (like Rogue AV problems), with abuse the dealerships can't possibly warranty, or kvetch about the legitimately high costs of running a dealer shop (you don't wnat to know what our "required equipment" costs, there's over $200K worth just in our tire bay. I don't even want to think about the tool room).

[macgiver]

again VStar , you hit the nail on the head again............. " diatribe " ........I practically flunked English ,as ALL can see ????

[mellotron]

Thanks for the advice! I'm working my way through the list of stuff to check. Not as simple of a system as they make it out to be. I'll update when I have some results.

[VStar650CL]

Thanks for the advice! I'm working my way through the list of stuff to check. Not as simple of a system as they make it out to be. I'll update when I have some results.

You're most welcome. No, purge system issues can be a real PITA to diagnose because there are so many ticky physical issues that can be responsible, not just electrical issues or failed parts. I'll admit it's one of my most un-favorite diagnostic tasks.

[mellotron]

An update ... I performed all the checks I could with the tools that I have, and no luck. I was talking to my wife's cousin last week, who runs a shop nearby, and he insisted that his master tech could figure it out. So I drop the car off and they run their "detailed scan" and insist that we had a bad purge valve put in (it wasn't holding quite good enough vacuum or something vague like that). I told them to go ahead and replace it. Got a call today, surprise surprise, that didn't fix it. They now think there's a problem with the ECM, and it's beyond their expertise. I can't pick it up until tomorrow, so I have yet to find out how much they're going to charge me to not have fixed it. I'll be a little ticked off to pay twice for the exact same non-fix.

With that good news, I then spoke with a nearby dealership service department. Well not really nearby, the local Nissan dealership is awful, so I'm going to one that's 2 hours away. They said they can run diagnostics deeper than the guys that have it now, and are confident they can figure it out, which is the same thing the guys that have it now said. I have an appointment in a couple weeks at the dealership. I'm looking forward to being told we have to replace the ECM.

[D1dad]

That sucks. I’d shop for a junk yard ecm and have Nissan program it. If not be prepared for major sticker shock. My coworker spent $1600 at the dealer when his daughters went out when she was away at college. Her car was a 2012 Altima which I assume is gonna be in the same ballpark.

[VStar650CL]

That sucks. I’d shop for a junk yard ecm and have Nissan program it. If not be prepared for major sticker shock. My coworker spent $1600 at the dealer when his daughters went out when she was away at college. Her car was a 2012 Altima which I assume is gonna be in the same ballpark.

+1. Don't go by the Nissan part number, though. If you google that, you'll only get new ones. Take a pic of the sticker on the ECM and use the Hitachi p/n to search for a used one. If I remember right, on an early gen2 it should be something like BEM4xx-xxx. There will be a lot of other numbers but they're firmware and date codes that won't matter, you'll need to have it reprogrammed anyway. Be aware that the car won't start until the keys are reprogrammed, so if you DIY it, you'll need to tow it to the dealer for repro.

[D1dad]

I just looked one up at the place I trust to actually sell the part they advertise and it was $65 off a 2013 with 37k. I’m sure you’d have similar luck as well. Even after the dealer charges you to program it your still saving hundreds if not a grand.