2005 supercharged 3.8 grand Prix issues

Asked by Jan 28, 2016 at 12:05 AM about the 2005 Pontiac Grand Prix GTP

Question type: Maintenance & Repair

I have 2005 grand Prix gtp with the SUPERCHARGED 3.8. With 88k miles I replace the
lower intake gasket & scharger gasket cuz of lack of power an codep0300 mult random
missfire . didn't help changer coils even swapped off a buddy's car still nothing. Changed
the cat for bout 2 weeks car ran quite nice went back to doing the same thing. Tue cat
was the mid grade version that Napa offered ran like 375$ I believe part only. What's
going on? Also now cuz of money issues had to continue driving the car I've got lifter
noise. How much difference will I see if I hollow the cat out or put straight pipe in? All
suggestions welcomed

6 Answers

Well did you try the direct fit cat cause Napa has a mid grade like yu said ?

There is a vacuum line in back of the supercharger look at the vacuum line and see if it is collapsed if so the is you problem

I had a reduced power code and it turned out to be the vacuum lines that run from the super charger. Only 20 CAD from gm

The vacuum line is fine. That was the first thing I changed

Yes the cat was a direct fit.I have read on some gp forums that the last ten GPS have issues with aftermarket cats. That the supercharger versions clog up everything except for oem. There's gotta be a cheaper option than the 1000$ gm cat though.

If you want to try a high flow cat I would suggest zzp. http://zzperformance.com/3800/exhaust.html I've been using there's for 50000 kms and no codes yet. It's $130 USD plus shipping.

Your Answer

Add photo

Related Questions

  • What is the max milage that a Grand Prix can get? 45 answers

    My grand prix is a 99 and it has 119,000 miles on it. How much longer can it go?

    1999 Pontiac Grand Prix 4 Dr GT Sedan

    -

    Maintenance & Repair

  • 2005 Pontiac Grand Prix

    I have an '05 Pontiac Grand Prix base model car, an recentley done an engine swap and got the engine, transmission, and brain out of a GTP. Is there a way I can go around not having the on board co...

    2005 Pontiac Grand Prix Base

    -

    Maintenance & Repair

  • is a Pontiac Grand prix 97 3.8l v6 w/o SC the same engine as the Grand prix GTP 3.8l With SC? 3 answers

    I have a 97 Pontiac Grand Prix GTP 3.8L SC and it Turned a Rod bearing and i was wondering if the 3.8l W/O SC out of a 97 Grand Prix GT will work in my GTP with my Supercharger? Is the block the same...

    1997 Pontiac Grand Prix 2 Dr GTP Supercharged Coupe

    -

    Maintenance & Repair

  • 05 grand prix engine into 04? 4 answers

    have an 04 with blown motor, have an 05 wrecked grand prix was going to swap motor into 04 but salvage yards says they don't interchange, they look the same looking at them from the top but scared to ...

    2004 Pontiac Grand Prix

    -

    Maintenance & Repair

  • supercharged grand prix 7 answers

    i have a 1999 grand prix with a non supercharged 3.8 v6. i thought that gm made a supercharged 3.8 for that model. i was just wondering if you could find a factory supercharger for that engine package...

    1999 Pontiac Grand Prix

    -

    Car Customization

Grand Prix

Looking for a Used Grand Prix in your area?

CarGurus has 3,749 nationwide Grand Prix listings starting at $879.

ZIP:

Search Pontiac Grand Prix Questions

Pontiac Grand Prix Experts

#1 Js08016
Js08016
Reputation 3,980
#2 Tom Demyan
Tom Demyan
Reputation 2,660
#3 munron
munron
Reputation 2,070
View All

Related Models For Sale

Used Chevrolet Impala
799 Great Deals out of 34,708 listings starting at $799
Used Pontiac Bonneville
6 Great Deals out of 674 listings starting at $1,599
Used Dodge Charger
395 Great Deals out of 30,065 listings starting at $2,343
Used Chevrolet Monte Carlo
12 Great Deals out of 1,692 listings starting at $2,300
Used Pontiac G6
87 Great Deals out of 5,158 listings starting at $999
Used Pontiac Grand Am
1,665 listings starting at $1,995
Used Chevrolet Malibu
1,077 Great Deals out of 85,119 listings starting at $1,995
Used Pontiac GTO
11 Great Deals out of 488 listings starting at $6,500
Used Jeep Grand Cherokee
888 Great Deals out of 69,215 listings starting at $1,300
Used Ford Mustang
396 Great Deals out of 44,403 listings starting at $1,000
Used Honda Accord
887 Great Deals out of 82,090 listings starting at $999
Used Nissan Maxima
359 Great Deals out of 25,313 listings starting at $1,400
Used Chrysler 300
401 Great Deals out of 22,462 listings starting at $1,000