Misfires

Asked by Mar 25, 2017 at 10:13 PM about the 2003 Nissan Altima 2.5

Question type: Maintenance & Repair

Had a 3rd cylinder misfire. Changed the coil pack
on that cylinder. Ran great for two days. Started
back to idle rough & check it engine light flashing
when driving. Changed the spark plug on the 3rd
day. Runs good but, idles rough when you start &
stop. My next thought was fuel so, I bought some
Seafoam fuel conditioner & added it to 1/4 tank of
gas. My old lady has driven the car back forth to
work the last two days but only 5 miles round trip!
So my question is,  do you think if I drove the car
on the highway for 30 miles or so that should help
right?  And if not, what will?

1 Answer

73,065

Possible causes; Faulty spark plug 3, Clogged or faulty fuel injector, 3 Faulty ignition coil 3, Fuel injector 3 harness is open or shorted, Fuel injector 3 circuit poor electrical connection, Ignition coil 3 harness is open or shorted, Ignition coil 3 circuit poor electrical connection, Insufficient cylinder 3 compression, Incorrect fuel pressure, Intake air leak...The P0303 code means that the cylinder 3 is misfiring or is randomly misfiring. Start by checking for intake leaks an if no leaks are found the next step is to replace the spark plugs on cylinder 3. If the problem persist more tests needs to be done to diagnose problem.

Your Answer

Nissan Altima Experts

  • #1
    Tom Demyan
    Reputation
    2,120
  • #2
    putolile
    Reputation
    700
  • #3
    Cassie Sapphire
    Reputation
    680
View All

Related Models For Sale

Used Nissan Maxima
29 Great Deals out of 324 listings starting at $3,976
Used Honda Accord
62 Great Deals out of 1,114 listings starting at $748
Used Toyota Camry
42 Great Deals out of 1,593 listings starting at $1,700
Used Honda Civic
307 Great Deals out of 4,113 listings starting at $1,494
Used Nissan Sentra
161 Great Deals out of 1,751 listings starting at $1,987
Used Hyundai Sonata
46 Great Deals out of 1,292 listings starting at $1,781
Used Toyota Corolla
161 Great Deals out of 3,413 listings starting at $2,394
Used Chevrolet Malibu
110 Great Deals out of 2,268 listings starting at $2,500
Used Kia Optima
41 Great Deals out of 762 listings starting at $1,232
Used Chevrolet Impala
61 Great Deals out of 938 listings starting at $1,900
Used Hyundai Elantra
156 Great Deals out of 3,443 listings starting at $2,490

Used Cars For Sale

2017 Nissan Altima 2.5 For Sale
15 listings starting at $22,323
2016 Nissan Altima 2.5 For Sale
7 Great Deals out of 29 listings starting at $14,599
2015 Nissan Altima 2.5 For Sale
35 listings starting at $13,495
2014 Nissan Altima 2.5 For Sale
12 listings starting at $9,900
2013 Nissan Altima 2.5 For Sale
3 Great Deals out of 68 listings starting at $9,999

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.