RX - 3rd Gen (2010-2015) Discussion topics related to the 2010 - 2015 RX350 and RX450H models

MAF Permanent Code After Spark Plug Exchange

Thread Tools
 
Search this Thread
 
Old 03-30-24, 11:07 PM
  #1  
khris
10th Gear
Thread Starter
 
khris's Avatar
 
Join Date: Mar 2024
Posts: 10
Likes: 0
Received 1 Like on 1 Post
Default MAF Sensor Permanent Code After Spark Plug Exchange

Had spark plugs swapped out for 120k mile maintenance. Mechanic removed and reinstalled intake manifold to get to rear plugs. I’ve had a stored permanent Mass Air Flow Sensor code since (10 days). Code is P0102 - Mass or Volume Air Flow Sensor “A” Circuit Low.

There is no engine light on and car runs exactly as it did before the plugs were replaced. I’ve driven the car every day (roughly 10-25 miles per day).

Mechanic said that the code should clear itself and that if the CEL is not on that it’s not a big deal. There were a few other related codes which cleared within a few days but this one has stuck.

Q:
1. Shouldn’t the permanent code have cleared itself by now?

2. Does this require any attention or is mechanic correct?



Last edited by khris; 03-31-24 at 08:01 PM.
Old 04-02-24, 07:34 PM
  #2  
afpj
Instructor
 
afpj's Avatar
 
Join Date: Jun 2008
Location: Nukewastedump
Posts: 804
Received 74 Likes on 59 Posts
Default

Odd codes pop up when you disconnect the battery. Use your bluedriver to clear that code, recheck after a drive. That type of code should set quickly if it was real. Also you can check fuel trims and see if they’re in proper range.
Old 04-02-24, 08:39 PM
  #3  
khris
10th Gear
Thread Starter
 
khris's Avatar
 
Join Date: Mar 2024
Posts: 10
Likes: 0
Received 1 Like on 1 Post
Default

I tried clearing with BlueDriver but get a message stating that permanent codes cannot be cleared. Also went back to mechanic. He tried clearing but again, no go. He said that he had accidentally started the car when the mass air flow sensor was not connected, hence the code. Two weeks of driving, still stored.
Old 04-03-24, 07:52 AM
  #4  
afpj
Instructor
 
afpj's Avatar
 
Join Date: Jun 2008
Location: Nukewastedump
Posts: 804
Received 74 Likes on 59 Posts
Default

Hmmm, you may not be able to clear that individual code, you may have to do the “all clear” code erase, which resets all your emissions too …not a big deal, unless you have an inspection coming up real soon. What are your fuel trims and maf readings (in g/s) at idle? If fuel trims are normal and the maf is reading at or about 3.5 g/s at idle, you should be ok. Maf should read higher as you rev. Fuel trims should not change all that much with rpm if just sitting on your driveway.
Old 04-03-24, 08:18 AM
  #5  
salimshah
Moderator
Forum Moderator
 
salimshah's Avatar
 
Join Date: Apr 2001
Location: Austin, TX
Posts: 15,669
Received 1,106 Likes on 995 Posts
Default

imho it is a false positive which your advanced reader is showing. As long as your CEL is not lit up, you can ignore it.

If you are driven to see all clear on your reader, I would explore owner's manual or contact the customer service of the manufacturer of the reader.

Salim
Old 04-03-24, 02:55 PM
  #6  
khris
10th Gear
Thread Starter
 
khris's Avatar
 
Join Date: Mar 2024
Posts: 10
Likes: 0
Received 1 Like on 1 Post
Default

In all honesty it’s not a big deal as long as I know that no damage is being done to engine/cat. I will give it more time to clear and check those readings. Thank you

Originally Posted by salimshah
imho it is a false positive which your advanced reader is showing. As long as your CEL is not lit up, you can ignore it.

If you are driven to see all clear on your reader, I would explore owner's manual or contact the customer service of the manufacturer of the reader.

Salim
Originally Posted by afpj
Hmmm, you may not be able to clear that individual code, you may have to do the “all clear” code erase, which resets all your emissions too …not a big deal, unless you have an inspection coming up real soon. What are your fuel trims and maf readings (in g/s) at idle? If fuel trims are normal and the maf is reading at or about 3.5 g/s at idle, you should be ok. Maf should read higher as you rev. Fuel trims should not change all that much with rpm if just sitting on your driveway.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
helpmeplz
IS - 2nd Gen (2006-2013)
6
06-22-22 02:15 PM
dquiles07
IS - 2nd Gen (2006-2013)
3
05-29-21 12:11 PM
VicFlo661
GS - 2nd Gen (1998-2005)
1
03-12-20 08:16 AM
Class
RX - 1st Gen (1999-2003)
4
03-02-16 03:44 PM
2redhots
GS - 2nd Gen (1998-2005)
6
01-24-07 02:45 AM



Quick Reply: MAF Permanent Code After Spark Plug Exchange



All times are GMT -7. The time now is 02:16 AM.