Performance & Maintenance Engine, forced induction, intakes, exhausts, torque converters, transmissions, etc.

94 lexus sc400 code 31 help

Thread Tools
 
Search this Thread
 
Old 02-01-24, 12:31 AM
  #1  
edmundprieto98
2nd gear
Thread Starter
 
edmundprieto98's Avatar
 
Join Date: Feb 2024
Location: Hawaii
Posts: 2
Likes: 0
Received 0 Likes on 0 Posts
Default 94 lexus sc400 code 31 help

My sc runs rich with a strong fuel smell, harsh vibrations, and it sounds noticeably louder than normal. I thought it was just a simple misfire so I replaced the spark plugs, ignition coils, distributor cap & rotor, 1 fuel filter, and the fuel pressure regulator. After that, I finally get a code 31.
I know code 31 has something to do with the MAF sensor so I replaced that with a new one but STILL that didn’t fix it. She runs better with it unplugged.
Could it be the ECU?? PCV valve?? I am out of ideas please help!
Old 02-01-24, 05:58 AM
  #2  
Tallyhoe
Advanced
 
Tallyhoe's Avatar
 
Join Date: Feb 2020
Location: CA
Posts: 572
Received 136 Likes on 107 Posts
Default

Originally Posted by edmundprieto98
My sc runs rich with a strong fuel smell, harsh vibrations, and it sounds noticeably louder than normal. I thought it was just a simple misfire so I replaced the spark plugs, ignition coils, distributor cap & rotor, 1 fuel filter, and the fuel pressure regulator. After that, I finally get a code 31.
I know code 31 has something to do with the MAF sensor so I replaced that with a new one but STILL that didn’t fix it. She runs better with it unplugged.
Could it be the ECU?? PCV valve?? I am out of ideas please help!
If your ECU hasn't been serviced, I would heavily consider this before you throw more parts at it. Hope you didn't throw away your original MAF sensor. I would contact Tanin and get your ECU serviced. There are other places you can contact to get the ECU serviced, but I don't know them off the top of my head.
Old 02-07-24, 12:29 AM
  #3  
edmundprieto98
2nd gear
Thread Starter
 
edmundprieto98's Avatar
 
Join Date: Feb 2024
Location: Hawaii
Posts: 2
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by Tallyhoe
If your ECU hasn't been serviced, I would heavily consider this before you throw more parts at it. Hope you didn't throw away your original MAF sensor. I would contact Tanin and get your ECU serviced. There are other places you can contact to get the ECU serviced, but I don't know them off the top of my head.
The previous owner had the ecu rebuilt only 2 years ago. Could it be that its faulty again? Also, I already went through 2 MAF sensors and the car is still giving me problems
Old 02-08-24, 01:05 PM
  #4  
Tallyhoe
Advanced
 
Tallyhoe's Avatar
 
Join Date: Feb 2020
Location: CA
Posts: 572
Received 136 Likes on 107 Posts
Default

Originally Posted by edmundprieto98
The previous owner had the ecu rebuilt only 2 years ago. Could it be that its faulty again? Also, I already went through 2 MAF sensors and the car is still giving me problems
I'm starting to have issues with my rebuilt one... Tanin is suggesting new ECU... Since they haven't encountered my issue.. I would dig into a maintenance issue before you dig back into the ECU.
Old 02-09-24, 10:43 AM
  #5  
TaninAuto
Sponsor
 
TaninAuto's Avatar
 
Join Date: May 2012
Location: WI
Posts: 1,057
Received 110 Likes on 80 Posts
Default

This is accurate as we have never observed a code 31 MAF related problem coupled with any ECU problems or issues, or present prior to an ECU rebuild.

You can certainly send it in for diagnosis and we can use our test vehicles to confirm or deny the same issue you are having. 9 times out of 10 when we do this our vehicles run fine with no codes present.
__________________
TANIN AUTO ELECTRONIX
262-456-4147
contact@taninauto.com
www.taninautoelectronix.com

Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
amaterasu
ES - 1st to 4th Gen (1990-2006)
8
10-02-23 09:34 AM
Kce
Performance & Maintenance
8
07-05-22 11:55 PM
amysunkist
GX - 1st Gen (2004-2009)
5
08-03-19 06:37 PM
lexus400sc
SC- 1st Gen (1992-2000)
6
09-17-10 03:38 AM
lexus400sc
Florida Lexus Club
3
09-16-10 02:07 PM



Quick Reply: 94 lexus sc400 code 31 help



All times are GMT -7. The time now is 09:29 AM.