Butane
Member
- Car
- 2015 Q50 2010 G37 2014 QX70
- Name
- Jer
Hi,
My new to me 2014 Qx70 has 210,000 miles on the dash, I am trying to work through this issue I have noticed. I unfortunately cant confirm if this was a previous issue prior to all the work or not, I remember when I first purchased the car they told me a maf sensor was bad and that was throwing a code, as it has been some time and I have done a lot of work to the car I dont remember if the maf being bad was causing the same symptom since I replaced it with a new one and was on my way. The issue I am facing is that the engine has a stutter/Missfire every few seconds. The intervals are frequent but sometimes it may go a few minutes without it. Its not too noticeable while driving above 40 mph but any slow speeds or idle and you will feel it. Basically the whole vehicle shakes a bit like as if you tap the breaks while rolling and there is a audible change in the engine resonance for a second while the stutter happens. I am not throwing any missfire codes for this and with my current battery issue the codes have been cleared several times.
Since this is the same platform as a G37, Older model Q50, and 370z I have been perusing around in those forums as well and have seen a few possible solutions that I will list.
I am having issues with my battery currently, It is either bad, not charging correctly, or being drained very quickly. This could be through parasitic drain, bad wiring, or some error keeping the computer awake. One of these issues could be causing something else so Im leaving this as background info.
1. Maf sensors, I purchased one new maf sensor to replace a previously faulty one that the old owner told me was bad. I did check the obd scanner and I remember there was a maf code and once I replaced it I believe it went away after clearing. I cant remember if when it had the maf code if the vehicle felt the same way but I am inclined to put in the old bad one, clean them both, swap in the new one, swap sides on the new ones, and lastly order a new one to see if any of these instances changes anything.
2. Issue with BCM - Long story and common issue but due to the sunroof leak it could have been exposed to water over time. This does not directly correlate but again electrical issues could cause weird things to happen so I will inspect it and brush any tarnish to make sure grounds are making proper connections.
3. I saw a obscure post in the q50 forum about how a evap canister filled with fuel and water and otherwise dirty caused this issue and that once it was cleaned the issue went away. Well I do know that previously the fuel pump was replaced on this vehicle by the old owner so makes sense if something was compromised during this.
4. A q50 post in their forum suggested that one needed to set the idle of the vehicle possibly using nisscan and with that the problem should be resolved.
5. The easiest and one of the first solutions I may try would be to swap the Spark plugs and coils out for new ones. Even though I do not have a code thrown for missfire I also do not have a high end obd scanner and it could be a slight missfire.
6. I saw on another post for q50 that there is a throttle body and maf sensor relearn that I can do. This will be the second thing I try after cleaning the throttlebodies and maf sensors.
With this any input is greatly appreciated and if any of you have tried any of these or encountered the same issue please let me know what got it resolved thank you!
Other possibly related issues;
Minor Coolant leak
Exhaust leak/ strong exhaust smell by drivers side
TCM
Battery for the vehicle is bad or alternator
My new to me 2014 Qx70 has 210,000 miles on the dash, I am trying to work through this issue I have noticed. I unfortunately cant confirm if this was a previous issue prior to all the work or not, I remember when I first purchased the car they told me a maf sensor was bad and that was throwing a code, as it has been some time and I have done a lot of work to the car I dont remember if the maf being bad was causing the same symptom since I replaced it with a new one and was on my way. The issue I am facing is that the engine has a stutter/Missfire every few seconds. The intervals are frequent but sometimes it may go a few minutes without it. Its not too noticeable while driving above 40 mph but any slow speeds or idle and you will feel it. Basically the whole vehicle shakes a bit like as if you tap the breaks while rolling and there is a audible change in the engine resonance for a second while the stutter happens. I am not throwing any missfire codes for this and with my current battery issue the codes have been cleared several times.
Since this is the same platform as a G37, Older model Q50, and 370z I have been perusing around in those forums as well and have seen a few possible solutions that I will list.
I am having issues with my battery currently, It is either bad, not charging correctly, or being drained very quickly. This could be through parasitic drain, bad wiring, or some error keeping the computer awake. One of these issues could be causing something else so Im leaving this as background info.
1. Maf sensors, I purchased one new maf sensor to replace a previously faulty one that the old owner told me was bad. I did check the obd scanner and I remember there was a maf code and once I replaced it I believe it went away after clearing. I cant remember if when it had the maf code if the vehicle felt the same way but I am inclined to put in the old bad one, clean them both, swap in the new one, swap sides on the new ones, and lastly order a new one to see if any of these instances changes anything.
2. Issue with BCM - Long story and common issue but due to the sunroof leak it could have been exposed to water over time. This does not directly correlate but again electrical issues could cause weird things to happen so I will inspect it and brush any tarnish to make sure grounds are making proper connections.
3. I saw a obscure post in the q50 forum about how a evap canister filled with fuel and water and otherwise dirty caused this issue and that once it was cleaned the issue went away. Well I do know that previously the fuel pump was replaced on this vehicle by the old owner so makes sense if something was compromised during this.
4. A q50 post in their forum suggested that one needed to set the idle of the vehicle possibly using nisscan and with that the problem should be resolved.
5. The easiest and one of the first solutions I may try would be to swap the Spark plugs and coils out for new ones. Even though I do not have a code thrown for missfire I also do not have a high end obd scanner and it could be a slight missfire.
6. I saw on another post for q50 that there is a throttle body and maf sensor relearn that I can do. This will be the second thing I try after cleaning the throttlebodies and maf sensors.
With this any input is greatly appreciated and if any of you have tried any of these or encountered the same issue please let me know what got it resolved thank you!
Other possibly related issues;
Minor Coolant leak
Exhaust leak/ strong exhaust smell by drivers side
TCM
Battery for the vehicle is bad or alternator
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