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Hi Guys
I've got a engine light recently. Auto Zone's code is P2240 and P0171 P0174, my own ODB reads P0444 P0171 and P0174. I changed Fuel Filter, disa valve, crank case vent kit, upper and lower intake boots, and etc. Pretty much everything relate to the vacuum leak. I'm thinking about the oxygen sensor is bad now. When engine idle with shift at "D" mode, it vibrates worse than usual. But I read other posts, people changed the oxygen sensor and still get the same codes. Any ideas?
 

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Doubt it is the O2 sensors.

You likely still have a vacuum leak. For P0171 & P0174 to trigger the fuel compensation has to be off by 10% or more.

You need to figure out what the fuel long term fuel trim valves are as well.

Suggest you read the first link below in my signature.

May sure you check you intake boots, make sure all your CCV hoses are in fact connected and you might have a cracked valve cover as well??

You mention P0444 which is the purge valve. It is likely a culprit as if it does not shut off it can lead to a big vacuum leak.

You might check out this link, you really need to purchase a scan tool or software that can read real time data - http://forum.e46fanatics.com/showthread.php?t=967204
 

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Long term fuel trim on a good car should be under 2%. Many will be between 2-3%. I prefer to see my cars under 2%, but sometimes is it not worth the time or effort to fight with trying to find what is causing the fuel trim to be around 3%.

Anything above 3% you should continue to look for issues, usually vacuum leaks.
 

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Droid device, Torque Pro for $5, get the additional plug ins and the $15 ELM327 ($15) or something similar from Amazon.
 

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ELM327 is a generic OBD to Bluetooth adapter. Be careful as there are a few ELM327 adapters, some are USB and some are Bluetooth.

There are smaller physically profile, but slightly more expensive OBD to Bluetooth adapters that will work. Some prefer the smaller adapter so it does not hit your leg if you leave the adapter in the ODB port while driving to log data.

Another option is to purchase a ODB extension cable for a few bucks more to allow the Bluetooth adapter to be put out of the way next to or under the seat.
 

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I am getting the same codes. It started out as intermittent, but now SES light has been on for a few days. I measured the resistance on the purge valve and got 30.4 ohms. It should be in the 20s, no?
OP, I doubt you will respond to this, but hey, worth a shot. Did you resolve your codes? Did you have to change out your purge valve?
@jfoj I send you a PM regarding my problem, did you see it?
 

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Since the migration of the site, PM's are all screwed up so I have not had any recently.

Anyway, I find that P0444 tends to require the Evap Solenoid to be replaced which is not cheap and there are not really any decent non dealer alternatives that I have seen.

Resistance seems high based on new solenoid measurements, but there can be internal bad connections that are heat related as well. Make sure to also pinch the female terminals closed slightly so there is a good solid electrical connection.
 

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Jfoj, there's a particular reason for disapperared STFT/LTFT after the swap of a DME with some tweaks??
Not sure I follow the question completely.

Assuming the DME swap was effectively the sane DME then the "tune" should not be a primary cause of things. Not sure what "tweaks" may have been performed.

If this is a European delivery vehicle, I have been seeing some of these cars with slightly negative Fuel Trims, not sure 100% why because I do not have enough info on what may differ on European models.

At the end of the day, the MAF and O2 sensors are the primary sensors that control the fuel delivery, while there are other sensors that provide input, the MAF and O2 sensors are the key sensors.

But changes in fuel pressure, injector size and other non monitored or controllable things can shift/alter Fuel Trims. One overlooked thing on many of these cars is the Baro sensor which is built into the DME, some of these sensors go bad and usually trigger a code, but I do not know of any tool or software that can actually read the Baro sensor value in case the sensor has not failed 100%. Cannot say the Baro sensor is a problem or could be the problem, but just one of the sensors that is not front and center and could cause problems behind the scene.
 

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Not sure I follow the question completely.

Assuming the DME swap was effectively the sane DME then the "tune" should not be a primary cause of things. Not sure what "tweaks" may have been performed.

At the end of the day, the MAF and O2 sensors are the primary sensors that control the fuel delivery, while there are other sensors that provide input, the MAF and O2 sensors are the key sensors.
Sorry for being so synthetic..
both torque & odb fusion are not reading fuel trims, no wrong values just no read at all.
i' supposed that this could be a problem of SW deleted 02 but i've checked, pre are ON (and both apps are showing V reading) and post are OFF.
i was asking you (trim master) what else i can check, probably something has been disabled while tweaking the DME with MS42/43 wiki infos
can't go deeper as i'm noob in DME tune and a guy flashed this spare DME that i provided him (he also doesn't know why)
i've already checked with OEM DME (EU2) and everything is working proprely with that..
 

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Riddle,

The problem with not seeing Fuel Trim values may be with the OBDII wireless interface. Have seen some flaky OBDII wireless interfaces that work, but will not present all the available PID's.

Use OBDFusion and run a Diagnostic Report with the engine warm and idling. Save and post the Diagnostic Report for me to look at. It may give insight if the interface may be the problem.
 
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