Black smoke loss of power rpms jump all over

Asked by May 07, 2017 at 12:13 AM about the 2001 Pontiac Grand Prix GTP Coupe

Question type: Maintenance & Repair

I have a 2001 Pontiac grand Prix gtp
supercharged 3.8 liter v6 I have replaced the
IAC sensor tps sensor o2 sensors spark
plugs wires fuel filter and pump runs out of
gas at top of orange mark new mass air flow
sensor ecm new it still has the same
problem does anyone have the correct
answer of what exactly it is tired of wasting
money...Thanks

4 Answers

250

Check the cat and muffler

22,985

Check/test compression on all cylinders first and foremost to know if its worth any-more time/money. Running rich, fuel injectors may be dirty and to atomizing fuel any more.

1 people found this helpful.
286,605

I always diagnose before throwing parts at a vehicle. Is the Check engine light on? Scan for codes? Black smoke means running rich like engine creator mentioned. Is the car running on the cold side?

2 people found this helpful.
78,095

Definitely running rich. Fuel pressure regulator and/or fuel injectors leaking. These injectors are known for getting gumed up and becoming troublesome because of not spraying properly. Test the MAP sensor as well. A bad MAP sensor can make it go rich. What trouble codes do you have? With it running rich enough to produce black smoke, the service engine soon light has to be on! HTH. -Jim

Your Answer

Grand Prix

Looking for a Used Grand Prix in your area?

CarGurus has 1,802 nationwide Grand Prix listings starting at $2,500.

ZIP:

Pontiac Grand Prix Experts

  • #1
    Js08016
    Reputation
    4,650
  • #2
    Tom Demyan
    Reputation
    3,230
  • #3
    munron
    Reputation
    2,690
View All

Related Models For Sale

Used Chevrolet Impala
387 Great Deals out of 25,587 listings starting at $900
Used Pontiac Bonneville
324 listings starting at $3,395
Used Chevrolet Monte Carlo
924 listings starting at $3,900
Used Chevrolet Camaro
241 Great Deals out of 28,772 listings starting at $1,800
Used Ford Mustang
252 Great Deals out of 36,666 listings starting at $2,500
Used Pontiac Grand Am
697 listings starting at $2,500
Used Chevrolet Malibu
448 Great Deals out of 49,677 listings starting at $2,111
Used Pontiac Firebird
8 Great Deals out of 674 listings starting at $3,695
Used Jeep Grand Cherokee
771 Great Deals out of 75,753 listings starting at $899

Used Cars For Sale

2008 Pontiac Grand Prix For Sale
302 listings starting at $3,995
2007 Pontiac Grand Prix For Sale
281 listings starting at $2,770
2006 Pontiac Grand Prix For Sale
3 Great Deals out of 284 listings starting at $2,500
2005 Pontiac Grand Prix For Sale
240 listings starting at $4,995

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.