Sputter/backfire and sulfur foul smell on heavy acceleration

20

Asked by Oct 05, 2015 at 08:17 PM about the 2000 Pontiac Grand Prix GTP Coupe

Question type: Maintenance & Repair

Changed iac,maf,tps,fuel pressure
regulator,fuel pump, air filter, fuel filter,
csps, egr, oil change, exhaust
work(mufflers) and ignition module. Got the
car to stop stalling on start and runs great
besides odd idle and foul smell on heavy
acceleration. Only things I haven't changed
are plugs wires, coil packs and injectors. I
cant find an evap leak but line from gas cap
to fuel tank are rusty.

5 Answers

20

Also have codes p0102, 0440, 0306

1 out of 1 people think this is helpful.
1,515

Sounds like catalytic converter is getting bad.

63,055

P0102 is Mass Airflow Sensor circuit, low input. Possible bad connection or bad sensor. P0440 is an EVAP system leak. The system is leaking vacuum. Gas cap is #1 cause for this trouble code. P0306 is misfire on cylinder #6. Do you have an aftermarket air filter, such as a K&N, which requires oil? If so, get rid of it! The oil contaminates the Mass Airflow Sensor. The sulfur odor is most likely the catalytic converter overheating due to the misfiring on cylinder #6. HTH. -Jim

Best Answer
20

I do have an aftermarket air intake came with the car when I bought it 2 years ago have never oiled it just changed the cone filter on it about a year ago when I did the first maf sensor. I have gone through 2 maf sensors in the last year the second one about a month ago when I changed the iac , tps, and crank sensor. Also cleaned the throttle body while I was at it but didnt check any of the connections so ill take a tomorrow and get a new gas cap. As far as vacuum leaks I haven't been able to find one under the hood any of the times ive checked but im going to put a stock air filter on it and ill get back with the results. Thanks for the answers guy much appreciated!

1 out of 1 people think this is helpful.
63,055

Ok, sounds good. You're welcome. Glad to help. Thank you for the best answer click. -Jim

Your Answer

Add photo

Related Questions

Grand Prix

Looking for a Used Grand Prix in your area?

CarGurus has 2,896 nationwide Grand Prix listings starting at $879.

ZIP:

Search Pontiac Grand Prix Questions

Pontiac Grand Prix Experts

#1 Js08016
Js08016
Reputation 4,070
#2 Tom Demyan
Tom Demyan
Reputation 2,710
#3 munron
munron
Reputation 2,110
View All

Related Models For Sale

Used Chevrolet Impala
594 Great Deals out of 29,130 listings starting at $1,300
Used Pontiac Bonneville
522 listings starting at $1,695
Used Chevrolet Monte Carlo
10 Great Deals out of 1,414 listings starting at $2,500
Used Chevrolet Malibu
809 Great Deals out of 88,732 listings starting at $1,900
Used Pontiac Grand Am
1,309 listings starting at $799
Used Chevrolet Camaro
144 Great Deals out of 35,537 listings starting at $1,995
Used Ford Mustang
314 Great Deals out of 45,661 listings starting at $2,000
Used Nissan Maxima
277 Great Deals out of 26,136 listings starting at $2,545
Used Pontiac Firebird
9 Great Deals out of 791 listings starting at $1,800
Used Nissan Altima
805 Great Deals out of 78,280 listings starting at $470

Used Cars For Sale

2008 Pontiac Grand Prix For Sale
10 Great Deals out of 430 listings starting at $2,495
2007 Pontiac Grand Prix For Sale
5 Great Deals out of 427 listings starting at $1,200
2006 Pontiac Grand Prix For Sale
4 Great Deals out of 445 listings starting at $1,999
2005 Pontiac Grand Prix For Sale
352 listings starting at $2,999