Hi,

I've driven a 2001 S2000 over the same route for 10 years. I know when the temp gauge goes from 1 bar to two to three. I know where to set the interior heating control **** to make the car comfortable on a cold day.

Recently I've had to drive farther and farther before the temp gauge goes from one bar to two bars and then to three bars. I've had to turn the interior temp **** from the 12 o'clock position (1/2 cold, 1/2 warm) to full hot. Then after 5 miles to the 3pm position. The air coming from the heater is not as hot as it used to be.

I thought - no problem, the thermostat failed, stuck open. So I had the dealer change it. Absolutely no change. I am now driving 1.6 miles at 30-40mph to get to three bars at ambient 50 degreesF, and the heater **** is set all the way hot on a 12 mile drive. Last year heater **** all hot would have cooked me.

What other than a stuck open thermostat would cause the car to take longer to warm up and then to run colder ?

What is the right diagnostic procedure ?

Thanks. S2K is a 2001 with 65K miles, stock everything.

 

what... lol

try a jacket ?

 

these are the kinds of issues that come in to my dealership and i contemplate ending myself.

 

So whats the problem?

 

Anybody have any diagnostic thoughts? It's bad to run engine below temp, if it is actually below temp.

Objectively, the heater **** is turned much farther and I get a mile farther down the raod then i used to before getting 3 bars on the temp gauge. Wish it had numbers.

Anyone ?

 

clogged heater core

 

That doesnt explain why the engine temp gauge isnt heating up as fast either.

Bad thermostat - it isnt shutting so it's running coolant through the radiator at all times. Get a new one.

 

he already got it replaced. OP if you are really bothered by this go to the dealership and ask them what the correct coolant to water ratio is, they can also check the ratio. however, ambient temperature/air/humidity is also a factor.

 

Hi, thanks for the replies and discussion. Yes, replaced thermostat. Yes, had system flushed and new coolant. (For the poster "...come in to my dealership and i contemplate ending myself. " agree totally, have not told dealer that thermostat replace made no difference).

Is there any easy way to verify the engine is getting up to correct temp? If so then I like the 'clogged heater core/something clogged in heater air passages' thought coupled with 'I just imagined it took the car longer to heat up'. I was afraid there was something basic i was missing, my knowledge of cars ended with carbs. I can't think of how the engine can't be getting to temp with a good thermostat.

 

You can check to make sure the heater control solenoid is opening properly (ie, its only half way open even though the **** is turned full hot).

I'm not the first person to put in a "new" thermostat only to find it doesn't work. Aftermarket thermos suck and it's possible that the dealership didnt have one in stock so they went down to the local parts place and picked one up. It's also possible that the tech was behind and never replaced your thermostat. Wouldnt be the first time a shop claimed to do work they didnt.

Easy way to verify the engine is getting to temp - Borrow and OBD 2 scanner and it should output the actual engine temp (vs the stupid bars).

 

nice: "Borrow and OBD 2 scanner and it should output the actual engine temp "

Ordered one of the $50 ODB2 to PC devices. Should be able to log coolant temp real time and see it warm up while driving. Will either point to bad thermostat, or make me happy that all is well. Great suggestion. Think thermostat is 180F on S2K. Guess I should see temp rise above 180 then hover near 180? Or be in neighborhood of that plus/minus 10? Or is operating range much rougher ?

 

i would bet that it is something funky going on with the valve that lets hot coolant get into the heater core.

at least everything is still working correctly though.

 

Yes, car running great. Pulls stronger than ever. The ODB2 tool came today. VB playoffs tonight, so will prob be wed before i can try it out. will post results when i get them.

 

before u go bonkers see if your heater control valve is giving you full travel while opening and closing, try a coolant flush.... check coolant level, do you smell coolant anywhere?? put a temp gauge in your vent and see what temp the air coming out is. just a few idears keep me posted

 

mumm this shoe tastes good.

took a few minutes to get a good connection between the tool and the car computer. Temp gauge was at two bars already by the time laptop was recording temp graph. Temp still too slow. Drove for maybe 1/4 mile slowly. Temp came PERFECTLY up to 180 and stabilized. After giving the rest of the car a chance to warm up too i went up and down a few hills, accelerated up hills, idled down hill, perfect. Temp stayed in narrow range from 170s to 190s.

 

?

 

I was thinking the same thing, its very easy to adjust and can make a drastic difference in you AC and heater temps

 

honda's with a little age on them have an issue with the screw on the top of the hot water valve strip out while you see it actually moving along with the motion of the a/c controls its not moving the valve itself check that, check heater core clogging i have a feeling the coolant temp on the cluster is not relievent to your issue unless you have really documented what it did not just what you remember happening it might not be totally correct

check inlet and outlet temp of the coolant from the heater core, check the difference in temp on the upper and lower hoses and go over the overall health of the cooling system from hoses to cap to overflow just as a general checks after all most goofy issues are often the simpilist things

to whomever claimed this is why they want to end theirselves becuase these are the complaints they get at their dealer....get out of this business you can't take it leave it to those who give a **** about customer complaints and your one of the reasons the masses hate dealerships i don't need you ruining my good name

 

Baby its cold outside (or colder, or you're getting older).