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

92,535

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.

92,535

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

Add photo

Related Questions

  • Running Hot 10 answers

    My car runs great. The oil looks greats. I have plenty of water in it but today on my way home ; it started running hot. I need to know what's wrong because I have to get to work.

    2002 Pontiac Grand Prix GTP

    -

    Maintenance & Repair

  • 20004 Gran Prix Supercharge that runs hot 4 answers

    My 04 Gran Prix keeps running hot. I've had a new thermmostat put on it, had radiator flushed and cooling fans checked. I owned a 98 Gran Prix that I had the same problem with. Never found out what wa...

    2004 Pontiac Grand Prix

    -

    Maintenance & Repair

  • Hot coolant 4 answers

    Here's the problem. -hot coolant light on -after I stop the car at a stop light had issue to accelerate forward. What do I need to do guys?

    2005 Pontiac Grand Prix GT

    -

    Maintenance & Repair

  • Temp question 98 grand prix 22 answers

    I have a 98 Grand Prix that I replaced the engine with one from a 2001 buick regal. I put in a new 160 fail safe thermostat. When driving non stop, the temp gauge barely moves, but if I drive in sto...

    1998 Pontiac Grand Prix 2 Dr GT Coupe

    -

    Maintenance & Repair

  • Also, have a 1997 trans-am running hot 13 answers

    Car runs great any speeds above 40 or 50mph. But once at freeway speeds for around 20 or 30 mintues, then incounters stop & go traffic, the temp will creep up, during the stop goes to over 240 and...

    Pontiac

    -

    Maintenance & Repair

Grand Prix

Looking for a Used Grand Prix in your area?

CarGurus has 2,867 nationwide Grand Prix listings starting at $1,500.

ZIP:

Search Pontiac Grand Prix Questions

Pontiac Grand Prix Experts

#1 Js08016
Js08016
Reputation 4,160
#2 Tom Demyan
Tom Demyan
Reputation 2,830
#3 munron
munron
Reputation 2,180
View All

Related Models For Sale

Used Chevrolet Impala
587 Great Deals out of 31,590 listings starting at $799
Used Pontiac Bonneville
3 Great Deals out of 536 listings starting at $1,799
Used Pontiac Grand Am
1,222 listings starting at $1,999
Used Chevrolet Monte Carlo
20 Great Deals out of 1,393 listings starting at $1,995
Used Pontiac GTO
7 Great Deals out of 455 listings starting at $6,000
Used Ford Mustang
458 Great Deals out of 45,660 listings starting at $1,999
Used Chevrolet Malibu
915 Great Deals out of 79,618 listings starting at $1,500
Used Chevrolet Camaro
214 Great Deals out of 30,774 listings starting at $1,217
Used Honda Accord
830 Great Deals out of 85,682 listings starting at $988
Used Pontiac Firebird
10 Great Deals out of 732 listings starting at $3,875

Used Cars For Sale

2007 Pontiac Grand Prix GT For Sale
3 Great Deals out of 80 listings starting at $2,500
2006 Pontiac Grand Prix GT For Sale
81 listings starting at $2,675
2005 Pontiac Grand Prix GT For Sale
4 Great Deals out of 112 listings starting at $1,895

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.