Engine misfires what to do?

Asked by Harold Jul 15, 2021 at 01:32 AM about the 2005 Cadillac DeVille Sedan FWD

Question type: Maintenance & Repair

my OBD list code as P0300 ( random multiple cyln. misfire detected). I have
replaced the coils, plugs, injector wire harness, fuel filter, air filter. Also had the
fuel injectors cleaned and new seals installed. The MAS was cleaned with the
correct spray as well the throttle body was sprayed with it's own correct spray.
Still idles and runs very rough. what's next ? ECM/PCM, knock sensor ??????

3 Answers
3,450

Justin answered 3 years ago

Vacuum leak? Run a timing check? Make sure you have the plug wires connected correctly

Mark helpful

F_O_R answered 3 years ago

Possible Northstar head gasket/head bolt failure.

1 people found this helpful.
Mark helpful

Your Answer:

Related Questions

DeVille

Looking for a Used DeVille in your area?

CarGurus has 204 nationwide DeVille listings starting at $3,995.

ZIP:

Own this car?

Share your experience with others.

2005 Cadillac DeVille

Write a car review

Review another car

Shortcuts

Search Cadillac DeVille Questions

CarGurus Experts

  • #1
    James Sparrow
    Reputation
    4,100
  • #2
    tuff4x4
    Reputation
    3,120
  • #3
    Cynthiasmith
    Reputation
    2,840
View All

Know more, shop wisely

Search

Related Models For Sale

Used Cadillac DTS
15 Great Deals out of 348 listings starting at $2,380
Used Cadillac Seville
38 listings starting at $6,995
Used Cadillac CTS
66 Great Deals out of 1,248 listings starting at $3,500
Used Cadillac Escalade
365 Great Deals out of 6,633 listings starting at $3,995
Used Chevrolet Corvette
626 Great Deals out of 9,990 listings starting at $3,000
Used Lincoln Town Car
10 Great Deals out of 348 listings starting at $2,999
Used Mercedes-Benz S-Class
283 Great Deals out of 6,379 listings starting at $3,950
Used Chevrolet Impala
195 Great Deals out of 3,485 listings starting at $1,995

Used Cars For Sale

2005 Cadillac DeVille Sedan FWD For Sale
16 listings starting at $3,995
2004 Cadillac DeVille Sedan FWD For Sale
17 listings
2003 Cadillac DeVille Sedan FWD For Sale
19 listings
2002 Cadillac DeVille Sedan FWD For Sale
14 listings
2001 Cadillac DeVille Sedan FWD For Sale
5 listings

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use. Content will be removed if CarGurus becomes aware that it violates our policies.