1996 GMC Jimmy engine warms up

LOANSHARK_08

MEMBER
1996 GMC JIMMY
6 CYL
4WD
AUTOMATIC
169,000 MILES

SO MY AC BLOWS ICE COLD ON THE HIGHWAY BUT WHEN I COME TO A TRAFFIC LIGHT THE TEMP GAUGE GOES TO HALF WAY OR A LITTLE HOTTER THE AC CUTS OUT THEN THE ENGINE ROARS LOUD AS IF A FAN IS KICKING ON AND COOLING IT OFF WHICH IT WILL COOL DOWN BUT ONLY WHEN I START DRIVING IF I DONT RUN THE AC IT RUNS PRETTY NORMAL IN BETWEEN COLD AND THE HALF MARK THAT ROARING NOISE ALSO HAPPENS IN THE MORNING THEN QUITS AND ENGINE SOUNDS NORMAL IT SEEMS LIKE A FAN CLUTCH OR A RELAY PERHAPS! WE JUST REPLACED THE AC COMPRESSOR AND CONDENSOR BUT IT STILL HAD THS PROBLEM BEFORE AND AFTER. PLEASE HELP ITS TOO HOT TO BE HAVING THSE PROBLEMS OR SHALL I JUST TRADE IT IN HAHA

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,885 POSTS

T noise you hear is the clutch fan kicking in. In the am it unlocks because it's cool. When it reaches a certain temp under the hood, it locks back up so the fan spins faster. It's notmal. As far as the engine temp, if it is running hot, you may want to have the cooling system flushed. I would say the thermostat, but you mentioned it runs normal without the ac on. Actually, it wouldn't be a bad idea to replace it too when the system is flushed. They are cheap.

Let me know if it helps.

Joe