So, I thought my car was overheating (the gague would go almost into the red), however I had the service manager where I work check it out one night, and it appears the engine fans are turning on fine...simply when the gague gets almost to the red. He checked the coolant temp when the fans turned on, and it was right about 225...so apparently my gague is inaccurate. I called my GM parts guy, and he said there are 2 sensors on top of the engine...one that reads the actual coolant temp and relays it to another sensor, which in turn relays that info to the ECM, and I assume the gague. With these sensors costing about $30 a piece, I imagine its worth it to replace both? Does one fail more often than another? Or is it more likely an issue with the gague?

Secondly, because I have to have the top end of the engine pulled apart anyway, I figured I would do a few preventative things while it was apart...replacing the radiator hoses (radiator is only a few years old), coolant, 160 thermostat (already has one), and I thought I'd switch to a Hypertech or JET lower-temp fan switch. Also, because the water pump is super rusty and I'm trying to clean up under the hood, I figured I'd replace the water pump with an aluminum one. Do more expensive ones like Edelbrock work better, or is a cheaper aluminum pump the same in terms of cooling ability? If so, does anyone recommend a specific brand?

Thanks to anyone who can help...

 

Sending unit for the gauge is in the driver's side head, between the # 1 and # 3 spark plugs.

 

His discription is a tad off, you have one sensor that the ecm uses, and one sending unit that the gauge reads from. They dont effect eachothers operation at all. Sounds like your gauge sending unit is bad. What type of induction are you running? Is this the tbi engine in your sig?

 

Yes, its the TBI...so I need only the gague sending unit? Works for me! Any other ideas on the other comments I had?

 

replacing the sending unit probably wont fix your gauge, they arent exactly accurate to any specific degree

 

Personally I would go with the Edelbrock,they flow way better than stock and the price isn't that bad at all.As far as your sending unit and sensor,for 30 bucks each it's worth changing both at the same time and see if that solves your problem.

 

I can attest to that. When I first got my car I'd be cruising around and my gauge would get really high, sometimes even into the red. I'd pull over, open the hood, and there would be no signs of overheating. The coolant tank wasn't boiling over, no steam, no nothing. The level of anti freeze would always just be at the "full hot" line. The only thing that alarmed me was that the fans weren't kicking on.

My gf's dad runs a dealership and I took it into him and told him what was going on. He tested it like your service manager did and he told me that when the needle was in the red the temp of the coolant was only at 205, which explained why the fans weren't kicking on. He let it run longer and the fans did end up kicking on. He replaced the sending unit and the gauge still does the same thing.

I got on here and asked around and learned that the gauges in these cars aren't the most accurate. Lots of people told me the best thing to do is to get an after market gauge and have it installed. I haven't done that yet though because my car is by no means a daily driver. I might put 250-300 miles on it in a year.

 

if you need a temp sending unit, lemme know. i have an extra, i believe...