hello I have a 99 pontiac grand prix

Asked by Mar 22, 2017 at 09:42 PM about the 1999 Pontiac Grand Prix 2 Dr GT Coupe

Question type: Maintenance & Repair

my 99 has been running rough for some time now, has service engine soon
light flashing most of the time when i drive it but occasionally will just stay on.  
I've replaced the spark plugs, wires, coils, fuel pump, and fuel fuses and still
runs ruff most of the time i drive it. anyone with good advice can you help me
out???

1 Answer

72,435

First thing is have the computer scanned for trouble codes. Most auto parts stores will do it for free. A flashing service engine soon light is warning you that the engine is misfiring and damaging the catalytic converter. It could be a number of things. Bad fuel injector(s), MAF sensor, faulty EGR valve, leaking intake manifold gaskets, faulty crankshaft sensor, etc. We'll need the trouble codes to see what's going on.

Your Answer

Pontiac Grand Prix Experts

  • #1
    Js08016
    Reputation
    4,470
  • #2
    Tom Demyan
    Reputation
    3,110
  • #3
    munron
    Reputation
    2,510
View All

Related Models For Sale

Used Chevrolet Impala
179 Great Deals out of 1,093 listings starting at $1,500
Used Chevrolet Monte Carlo
19 listings starting at $4,900
Used Ford Mustang
12 Great Deals out of 1,086 listings starting at $3,995
Used Chevrolet Malibu
121 Great Deals out of 1,862 listings starting at $999
Used Chevrolet Camaro
929 listings starting at $13,495
Used Pontiac Firebird
17 listings starting at $8,700
Used Jeep Grand Cherokee
131 Great Deals out of 3,621 listings starting at $3,500

Used Cars For Sale

2008 Pontiac Grand Prix For Sale
5 Great Deals out of 19 listings starting at $1,873
2007 Pontiac Grand Prix For Sale
9 listings starting at $4,990
2006 Pontiac Grand Prix For Sale
13 listings starting at $5,995

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.