I went into a dealership to ask about changing my thermostat to 170 degrees, and they told me that I should keep everything as stock as possible because then the sensors will probably get messed up and make the car run rich, along with the computer. Is this true?? They also told me that I should have kept my reflector that is under the car on because it creates a pocket of air that goes directly to the radiator. Do you guys agree?

My car is overheating so I got the following stuff:

~water wetter and distilled water
~hypertech 4028, on at 200 degrees and off at 185 degrees
~radiator cap
~Autometer water temperature gauge (I don't trust the stock one)

*How good is the stock fan or should I go aftermarket?

 

They were talking about your air dam under the car, which I'm guessing they were meaning your deflector, not reflector. And yes, it is a crucial part of your cooling system as if it's not on there, air isn't diverted to your radiator, therefore you will overheat.

 

Yup, lack of an air deflector can cause overheating, so put it back on. But if it was damaged, order a new one from the dealer--most deflectors are still available, it's the best way to be sure you're getting the correct part(cause there's a lot of different ones), it'll be priced the same as aftermarket replacements, there'll be no shipping cost, and you'll have it the next day. If the dealer can't get yours anymore, try www.yearone.com

Changing your stat won't hurt or mess-up anything, so no worries about that. But a dealer isn't likely to suggest anything different than spec, so that was the wrong person to ask. The stat/fan switch combo that you want to run should work well together. And since you already have it, give it a try and decide for yourself.

As for your fan, your stock fan is sufficient for daily use.

 

Thanks for your help

 

Putting in a cooler stat can make the car run too cool. If that happens your car wont go into closed loop and will run rich. If the cars running hot find out why dont use the thermostat to "fix" the problem.

 

But 170* isn't too cool. Closed loop occurs well below that, so you'll be fine.

But I agree that if the car's still running hot after you replace the air deflector there might be another problem, so keep one eye on your coolant level for awhile, keep another eye out for smoke, keep a third eye on your guage, and keep your nose tuned for coolant smell, lol. Oh, and keep your ears listening for your fan. So when you're at fan temp, check to be sure it's really working. Don't just assume it is.

 

Hello, I have a 1987 305 tpi and i went to go put in a 160 degree t-stat and i did not find any already installed. I put the stat in anyways and ran the car with it for a couple of weeks. It would heat up quite quickly after i installed it. Also ever sence I've done this my car hasn't ran correctly. I had to take off the throttle body to install the t-stat and when i took it off i ripped open one of the vacuum tubes going into the passenger side of the TB. I replaced the tube but it still isn't running right at idle. The engine many times will just stop when i depress the clutch. Unless i've been running the car for a little while. Would this be because I reset the computer? And as far as the t-stat should I be running with one?

 

Hi IROCAn87. I'm wondering how long you've run without a stat? How long have you had your car?

Going without a stat will work, obviously, but it's not recommended. And if your winters get cold, you'd want a stat so your engine will warm-up easier and stay up to temp, as you've learned it will.

But sorry to hear about the new problems. You shouldn't have had to remove the throttle body to replace your stat. But going by your new symptoms, it sounds like when you removed it, you might've affected either the Idle Air Control valve or the Throttle Position Sensor, both on the passenger side of the TB. A problem with one of those could produce a stalling problem. Did you remove those from the TB or just disconnect them? If you know that either were disturbed during your work, then you should check its adjustment.

Also, did you get the TB tightened up good when you reinstalled it? Gasket was good, and you gotta good seal? If not, you might have a vacuum leak there too.

Hope that's a start.

 

Well I've had the car for awhile about 2 years. I'm pretty sure the car has always been in arizona so i'm sure it was fine over the summer but there are times in the morning that it's pretty cold wich is about the same here in south carolina. As for the throttle body i had to take it off because the screws for the coolant neck or whatever you call it were not coming off the guy I think had used some blue lock tight on them. I'm sure the seal between the throttle body is good i cranked it down pretty hard but how do I check the throttle position sensor and the IAC sensor and make sure they're working probably. All I did was unplug them i did not remove them or adjust them at all. One last question, I was told there are three temperature sensors on my engine. One that sends the temp to the gauge inside( on the driver side under the header), One that is a switch to the fan(passenger side under the header) and the last one sends the temp to the ECM(that's supposed to be in the front of the engine somewhere) I can not find this sensor can someone explain to me where this is located?Thank You.

 

should be right on the intake manifold near the thermostat houseing. the one that sends to the ECM.

 

Oh, i searched for this topic and forgot to ask, where can you get a 170* thermostat. iv called a couple part stores around me and they dont even belive they exist haha. i live near Summit racing so ill go there, even though thier website cant find anything for a 170*.