P0401 code

Tiny
CANNON1349
  • MECHANIC
  • 1999 TOYOTA TACOMA
  • 2.7L
  • 4 CYL
  • 2WD
  • AUTOMATIC
  • 198,000 MILES
P0401 code continues to show up, even after replacing the EGR. Oddly enough the code doesn't show up for a while if mid-grade gas is used.
Tuesday, July 16th, 2019 AT 4:17 AM

3 Replies

Tiny
SCGRANTURISMO
  • MECHANIC
  • 4,897 POSTS
Hello,

In the diagrams down below I have included for you the factory diagnostic troubleshooting flowchart for Direct Trouble Code(DTC) P0401 for your vehicle. It will require you to use a multi-meter, so I have included this link below for you if you are unfamiliar with how to use one:

https://www.2carpros.com/articles/how-to-use-a-voltmeter

Please go through these guides, if needed, and get back to us with what you are able to find out.

Thanks,
Alex
2CarPros
Was this
answer
helpful?
Yes
No
Tuesday, July 16th, 2019 AT 6:20 AM
Tiny
CANNON1349
  • MECHANIC
  • 672 POSTS
Turned out they left the sensor for the EGR temperature unplugged. Now getting a p0402 code, ironically.
Was this
answer
helpful?
Yes
No
Wednesday, February 12th, 2020 AT 11:32 AM
Tiny
SCGRANTURISMO
  • MECHANIC
  • 4,897 POSTS
Hello again,

That is ironic and a little funny actually. But, in good spirits, I have included the diagnostic troubleshooting flowchart for your vehicle from the manufacturer for DTC P0402, with generic OBD2 scan tool testing. Please go through this guide and get back to us with what you find out.

Thanks,
Alex
2CarPros
Was this
answer
helpful?
Yes
No
Wednesday, February 12th, 2020 AT 3:40 PM

Please login or register to post a reply.

Sponsored links