Temperature runs hot when in traffic, cool at speed.

Asked by Jun 27, 2016 at 10:58 AM about the 2003 Pontiac Grand Prix GT

Question type: Maintenance & Repair

I just bought a 2003 Pontiac Grand Prix GT with 184k on it. After my initial drive home, I noticed a large puddle under the drivers side of the front bumper. I tasted it, and it had the sweet taste of antifreeze. There is still coolant in the reservoir. I drove it to work today (32 miles of freeway), and it ran cold, until I hit traffic, when it rose from 190ish to 225ish degrees. Then went back down when I got moving again. When I got to work, I didn't see a puddle, so I'm wondering if that was just excess coolant being expelled. Also wondering if it's normal for the 3800 Series II to fluctuate like that. Thanks!

4 Answers

107,375

Check the cooling fans operation, 225 is getting just too close to boilover and engine damage. You will notice some gauge movement like that once during the warming up cycle and then again in stop and go traffic, but just in cruse the gauge should remain stable at or around 195 to 200 degrees. The puddle is of some concern as there are only a few things that can leak that far out front even if it hit the lower core support and ran across to the drivers side. I would be checking the hoses and the radiator for signs of leakage.

Okay, so in traffic it's fairly normal? Because that is when it happens. At cruising speed (80MPH or so) the engine stays very cool. I'm taking it back to the dealer tomorrow morning to see if there's any leaks in the radiator or hoses, but I was just hoping it was spewing the excess or something. Still no signs of a puddle today, and there's still coolant in the reservoir.

107,375

In traffic yes the gauge swing is normal, just make sure the fans work as 225 is cutting it close, of course it could be a gauge reading slightly hotter than it really is, the shop should be able to plug in the the system and read what the sensors are really seeing.

Alright, good to know. I appreciate your help, man.

Your Answer

Grand Prix

Looking for a Used Grand Prix in your area?

CarGurus has 2,457 nationwide Grand Prix listings starting at $950.

ZIP:

Pontiac Grand Prix Experts

  • #1
    Js08016
    Reputation
    4,470
  • #2
    Tom Demyan
    Reputation
    3,120
  • #3
    munron
    Reputation
    2,550
View All

Related Models For Sale

Used Chevrolet Impala
559 Great Deals out of 33,307 listings starting at $1,499
Used Pontiac Bonneville
440 listings starting at $1,500
Used Chevrolet Malibu
1,067 Great Deals out of 57,948 listings starting at $995
Used Chevrolet Monte Carlo
7 Great Deals out of 1,220 listings starting at $1,125
Used Pontiac GTO
6 Great Deals out of 414 listings starting at $4,995
Used Ford Mustang
430 Great Deals out of 41,722 listings starting at $1,488
Used Pontiac Grand Am
975 listings starting at $2,595
Used Chevrolet Camaro
506 Great Deals out of 30,982 listings starting at $995
Used Nissan Maxima
348 Great Deals out of 20,620 listings starting at $1,175
Used Honda Accord
917 Great Deals out of 77,850 listings starting at $1,295
Used Pontiac Firebird
9 Great Deals out of 720 listings starting at $1,649

Used Cars For Sale

2007 Pontiac Grand Prix GT For Sale
50 listings starting at $2,400
2006 Pontiac Grand Prix GT For Sale
69 listings starting at $2,000

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.