Intermittent overheating

1999 ISUZU RODEO

164,000 MILES • 3.2L • V6 • 4WD • AUTOMATIC

HAILY2016

MEMBER
4 POSTS

My car overheated so I replaced the thermostat the radiator new fluid coolant. I flushed it I burped it and it still overheats. but only sometimes, sometimes it runs fine. but sometimes it will fluctuate temperature it will start to overheat go to high then seconds later the gauge will fall right back down to normal.

Jul 20, 2019 at 9:09 AM

SCGRANTURISMO

✓Experienced Mechanic
4,897 POSTS

Hello,

This could be a problem with your vehicle's water pump. If you look underneath of your vehicle's water pump there should be a little hole called a "weep hole". see if you can see if any coolant is leaking out of it. If it is then the water pump bearing has failed, or is failing, and the coolant is not being properly circulated. Here are a couple of links below for you to go to:

https://www.2carpros.com/articles/symptoms-of-a-bad-water-pump
https://www.2carpros.com/articles/water-pump-replacement

Please go through these guides and get back to us with what you are able to find out.

Thanks,
Alex
2CarPros

Jul 20, 2019 at 1:24 PM

HAILY2016

MEMBER
4 POSTS

Is a timing belt driven pump the same way? Wouldn't I have to remove the timing cover to even see the pump?

Jul 20, 2019 at 3:12 PM

HAILY2016

MEMBER
4 POSTS

There is is no noise coming from the engine, most of the time you cannot even hear it running.

Jul 20, 2019 at 3:27 PM

SCGRANTURISMO

✓Experienced Mechanic
4,897 POSTS

Hello again,

Yes, your vehicle's water pump is driven by the timing belt. It is still a fairly easy straight forward procedure to inspect, and if needed, replace it. I have included the step by step directions for this procedure in the diagrams down below. Please go through this guide and get back to us with what you are able to find out.

Thanks,
Alex
2CarPros

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