Why do it make a knockin sound every time step on the gass

Asked by Mar 15, 2016 at 07:20 AM about the 2004 Pontiac Grand Prix GTP

Question type: Maintenance & Repair

Under my hood of my 2004 grand pri it
makes a knocking sound

4 Answers

50,255

Possible low octain fuel, may want to try a tank of premium gas, or if the knock is low in the engine, then a rod bearing starting to go.

1 out of 1 people think this is helpful.
86,585

Bad rod, broken piston though these tend to make noise all the time, carbon build up on a piston, blown headgasket between two cylinders.

1 out of 1 people think this is helpful.
315

Possibly valve problems in your cylinder head or maybe loose or worn rod and main bearings, although your water pump on that model can also produce loud noise if failing.

625

Check for low oil. Harmonic balancers will knock as well when they are going bad.This is on the crankshaft pulley on the bottom of the engine.

Your Answer

Add photo

Related Questions

  • Dropping gas tank on 2008 Pontiac grand prix gpx 15 answers

    I have a 2008 Pontiac grand prix gpx and I was wondering how to get the gas tank off? Because someone sugared my gas tank. Also, I run it didn't no it was sugard, do U think it got in the motor?...

    2008 Pontiac Grand Prix GXP

    -

    Maintenance & Repair

  • 07'pontiac grandprix overheating low cabin heat 3 answers

    my car is overheating and has somtimes low or no heat , I have replaced water pump , thermostat , radiator I have flushed cooling system car does not over heat all the time heat works sometimes I am P...

    2007 Pontiac Grand Prix GT

    -

    Maintenance & Repair

  • my car starts up fine, but when I put it in drive and press the gass it just jerks forward. I'm hoping that it's not a transmission problem 1 answer

    Reverse works fine no problem there just when it's in drive

    1997 Pontiac Grand Prix

    -

    Maintenance & Repair

  • Car getting hot 2 answers

    Car was using antifreeze, but no leaks that I seen. Now it gets hot occasionally so I don't go far.well it's stalled now b/c it's wants to get hot, there's not any heat at all.if u put antifreeze i...

    2005 Pontiac Grand Prix GT

    -

    Maintenance & Repair

  • removeing speed limiter 66 answers

    how do you remove the speed limiter on the prix, i get to 110 and my engine boggs down to about 80 before i can start picking up speed again

    Pontiac Grand Prix

    -

    Car Customization

Grand Prix

Looking for a Used Grand Prix in your area?

CarGurus has 3,715 nationwide Grand Prix listings starting at $1,100.

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
792 Great Deals out of 34,371 listings starting at $799
Used Pontiac Bonneville
5 Great Deals out of 653 listings starting at $1,599
Used Chevrolet Monte Carlo
15 Great Deals out of 1,658 listings starting at $2,000
Used Pontiac G6
77 Great Deals out of 5,102 listings starting at $499
Used Pontiac Grand Am
1,644 listings starting at $1,995
Used Chevrolet Malibu
1,007 Great Deals out of 85,655 listings starting at $1,995
Used Pontiac GTO
10 Great Deals out of 484 listings starting at $6,500
Used Ford Mustang
363 Great Deals out of 44,352 listings starting at $1,000
Used Jeep Grand Cherokee
840 Great Deals out of 68,654 listings starting at $864
Used Nissan Maxima
345 Great Deals out of 25,215 listings starting at $1,400
Used Honda Accord
814 Great Deals out of 81,559 listings starting at $899
Used Chrysler 300
403 Great Deals out of 22,147 listings starting at $1,000