I have a 2004 Pontiac series 111,,ive changed plugs,coils wires,electonic ignition plate three times. All of that got rid of the miss,,however now im having a bogging between shifts between 1st and second only. Computer says catalytic converter flow restricted,however,could it be a problem going on before the converter? Could this be the map sensor giving a false read?

65

Asked by Jan 18, 2015 at 12:41 PM about the 2004 Pontiac Grand Prix GT2

Question type: Maintenance & Repair

although the trim is showing gt2,,my car is a gt series 111

2 Answers

67,445

Most likely the misfiring has ruined the catalytic converter. When an engine misfires the raw gasoline from that cylinder is sent from the engine, unburned, into the exhaust system where the catalytic converter must "eat" it. When this happens the converter is overheated and destroyed. The "honeycomb" inside the converter has melted and is now restricting the exhaust flow. HTH. -Jim

1 of 1 people found this helpful.
130

I have experienced the same issue. The misfire causes raw gas to expel into the catalytic converter and clogs it up. Are you showing any evap codes?

1 of 1 people found this helpful.

Your Answer

Add photo

Related Questions

Search Pontiac Grand Prix Questions

Pontiac Grand Prix Experts

#1 Js08016
Js08016
Reputation 4,270
#2 Tom Demyan
Tom Demyan
Reputation 2,870
#3 munron
munron
Reputation 2,210
View All

Related Models For Sale

Used Chevrolet Impala
592 Great Deals out of 34,064 listings starting at $899
Used Pontiac G6
91 Great Deals out of 4,082 listings starting at $1,650
Used Pontiac Bonneville
4 Great Deals out of 511 listings starting at $1,799
Used Pontiac Grand Am
1,183 listings starting at $1,599
Used Chevrolet Monte Carlo
20 Great Deals out of 1,419 listings starting at $1,995
Used Ford Mustang
537 Great Deals out of 45,845 listings starting at $1,999
Used Chevrolet Malibu
1,065 Great Deals out of 77,909 listings starting at $1,500
Used Pontiac GTO
4 Great Deals out of 465 listings starting at $6,000
Used Honda Accord
947 Great Deals out of 77,741 listings starting at $899
Used Nissan Maxima
321 Great Deals out of 24,382 listings starting at $999
Used Nissan Altima
1,154 Great Deals out of 79,677 listings starting at $500

Used Cars For Sale

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.