2004 Jeep Grand Cherokee P0420 and P0325

Tiny
GREENCHEVYMALIBU
  • MEMBER
  • 2004 JEEP GRAND CHEROKEE
  • 4.7L
  • V8
  • 2WD
  • AUTOMATIC
  • 140,000 MILES
STFT B1 -10.9%
LTFT B1 7.8%
STFT B2 -4.7%
LTFT B2 6.3%

Engine rpm 1472
Vehicle speed 40
ECT 210.2
MAP(inHg) 10.9

Knock sensor code doesn't always trigger.

I have a live data scanner. What should I look for?
Do you
have the same problem?
Yes
No
Friday, April 17th, 2015 AT 7:12 AM

4 Replies

Tiny
HMAC300
  • EXPERT
See pic for causes but with the converter being bad 420 code that may set it off as well. Converter probably needs to be replaced.
Was this
answer
helpful?
Yes
No
Friday, April 17th, 2015 AT 7:34 AM
Tiny
GREENCHEVYMALIBU
  • MEMBER
Would it better to replace both pre cats? Then just one?
Was this
answer
helpful?
Yes
No
Friday, April 17th, 2015 AT 8:33 AM
Tiny
GREENCHEVYMALIBU
  • MEMBER
Could the bad cat be causing the knock sensor code?
Was this
answer
helpful?
Yes
No
Friday, April 17th, 2015 AT 10:40 AM
Tiny
HMAC300
  • EXPERT
Teh cat system may be in one piece so both get replaced at same time. And that is what I ameant when I said the 420 code may set the other code.
Was this
answer
helpful?
Yes
No
Friday, April 17th, 2015 AT 12:06 PM

Please login or register to post a reply.

Recommended Guides