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

71,775

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
    4,460
  • #2
    Tom Demyan
    Reputation
    3,070
  • #3
    munron
    Reputation
    2,490
View All

Related Models For Sale

Used Chevrolet Impala
567 Great Deals out of 36,752 listings starting at $990
Used Pontiac Bonneville
475 listings starting at $3,499
Used Chevrolet Monte Carlo
9 Great Deals out of 1,238 listings starting at $1,488
Used Chevrolet Camaro
499 Great Deals out of 33,581 listings starting at $1,450
Used Pontiac Grand Am
1,036 listings
Used Ford Mustang
606 Great Deals out of 38,986 listings starting at $1,500
Used Chevrolet Malibu
1,161 Great Deals out of 67,659 listings starting at $880
Used Pontiac Firebird
10 Great Deals out of 767 listings starting at $2,500
Used Nissan Maxima
340 Great Deals out of 23,692 listings starting at $1,200

Used Cars For Sale

2008 Pontiac Grand Prix For Sale
7 Great Deals out of 392 listings starting at $1,750
2007 Pontiac Grand Prix For Sale
3 Great Deals out of 372 listings starting at $2,295
2006 Pontiac Grand Prix For Sale
409 listings starting at $4,850
2005 Pontiac Grand Prix For Sale
346 listings starting at $4,500

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.