1999 Toyota 4Runner Check Engine Light

Tiny
PEPO2K
  • MEMBER
  • 1999 TOYOTA 4RUNNER
  • 6 CYL
  • 4WD
  • AUTOMATIC
  • 177,000 MILES
After my check engine light went on, it was diagnosed as cat. System efficiency below threshold (P0420).

Replaced the front cat. Converter - light when back on after 6 days

Same code - replaced rear cat converter and sensor - light when on after 6 days

Same code - replaced front sensor - light went on after 3 days

Same code - replaced front cat. Converter again - light went on after 6 days

Could it be the computer?

Any suggestions would be appreciated. It's getting costly at this point.
Do you
have the same problem?
Yes
No
Wednesday, June 3rd, 2009 AT 10:01 AM

1 Reply

Tiny
TROYISBACK21
  • MEMBER
Replace all the oxygen sensors
Was this
answer
helpful?
Yes
No
Wednesday, August 5th, 2009 AT 12:01 PM

Please login or register to post a reply.

Recommended Guides