Thermostat supposedly replaced yesterday - but not working!!

[MLmotorsport]

Yesterday I took it in to a private shop that's had some NSX experience and a previous Acura tech. I bought the OEM thermostat from Dali a while back in preps for this service - but they said it was ok that I bought it elsewhere, but that they wouldn't warranty the part since I did. No problem... as long as they actually put that part in! Yesterday the car was still running a 1 tick under the middle after the service. I didn't think too much of it - But this morning i drove for about 6-7 mins before the needle even started to move and it was at least 10 mins before it got to the 1-tick-below-normal temp. The shop is closed today but I'm assuming they're going to claim that it's the parts fault when I call them on it. What should I do? Is there any way to tell if it's the old part when its removed?
thanks

 

[Briank]

You may have to bleed the cooling system. Was the dali thermostat a stock temp one?

 

[MLmotorsport]

Ya, it was a Honda part. The did change the coolant yesterday as well. But the thermostat is acting EXACTLY like it did before which why I replaced it... and why I'm thinking they put the old one back in *on accident*. Should I wait a few days to see if it starts acting normal? I did what the tech suggested to me yesterday to get the remaining air out - which was to leave it running for 30 mins after driving it.

 

[hlweyl]

I'm not sure I quite understand what is wrong with the car. Is the car overheating or do you lose temperature once the car is running? I have found the NSX does take a little longer to warm up compared to other cars.

 

[NSXTech]

What ambient temps are you driving in right now? Can you recall where the temp guage was during previous SAME ambient conditions. But most importantly, where does the gauge sit at a constsant highway cruise.

Make sure the climate control is OFF when you read the temp guage. With it on, unless you disable a/c, the front fan is running constantly and this will skewer readings down. Also, if the temp setting on CC is high, heater core will also bleed coolant temp for the same effect.

IMO, I am not sure you have a t-sat problem, but I am also unsure if I have enough data. The best way to assure parts replacement, is to ask for the old parts back. You may still request them, but if they say they are in the dumpster, they may be.
Or not.

HTH,
MB

 

[MLmotorsport]

It's not overheating, in fact it's "underheating". When the car is cold it takes a very long time for it to warm up (5 miles of driving as opposed to the maybe 1 mile it should take). It also never quite reaches the middle tick mark on the temp gauge (meaning the needle never get's horizontal - it's always pointing slightly downward when warm) no matter how long it's been running. That's a sign that the thermostat is bad from the research I've done.

 

[MLmotorsport]

What ambient temps are you driving in right now? Can you recall where the temp guage was during previous SAME ambient conditions. But most importantly, where does the gauge sit at a constsant highway cruise.

Make sure the climate control is OFF when you read the temp guage. With it on, unless you disable a/c, the front fan is running constantly and this will skewer readings down. Also, if the temp setting on CC is high, heater core will also bleed coolant temp for the same effect.

IMO, I am not sure you have a t-sat problem, but I am also unsure if I have enough data. The best way to assure parts replacement, is to ask for the old parts back. You may still request them, but if they say they are in the dumpster, they may be.
Or not.

HTH,
MB

Yesterday I drove it for about 3 hours in 55-60 degree weather and it didnt fully warm up (sits 1 mark below the center point which is exactly in the middle of hot(red) & cold(blue). This morning it was 50 degrees out and I wasn't running the climate control.
I think I've read almost every archive here about the thermostat symptoms and that definately seemed like the culprit; the heat takes FOREVER to get warm, the temp gauge needle takes 5 mins to even start moving after a cold start, and the gauge never reaches the temp it should.
Thanks for helping - I'd love to know if I'm missing something. They charged me $130 (just under 2 hrs) for t-stat replacement labor.

 

[Viper Driver]

My car runs about 1 tick under the center up to the center tick, depending on conditions. It also takes about 5 minutes to start warming up, because there is an on-ramp about 5 minutes from my house where the car is rarely warmed up in time for. My car has always been like this, and (from what I've read) this is completely normal.

Just from what I'm reading, I don't see where you have a problem. If your car was warming up in less than a minute before, I'd say that was the abnormal condition.

When the car is "not fully warmed up" (1 needle below the middle), does your ECU let you run the full RPM range?

 

[MLmotorsport]

My car runs about 1 tick under the center up to the center tick, depending on conditions. It also takes about 5 minutes to start warming up, because there is an on-ramp about 5 minutes from my house where the car is rarely warmed up in time for. My car has always been like this, and (from what I've read) this is completely normal.

Just from what I'm reading, I don't see where you have a problem. If your car was warming up in less than a minute before, I'd say that was the abnormal condition.

Man I hope you're right, but from what I read in the archives it's not normal according to some.

 

[MLmotorsport]

When the car is "not fully warmed up" (1 needle below the middle), does your ECU let you run the full RPM range?

I think it does allow me to go to full rpm's - but I'm going to wait another couple days before I rev that high because the coolant was changed just yesterday.

 

[nis350]

My car runs about 1 tick under the center up to the center tick, depending on conditions. It also takes about 5 minutes to start warming up, because there is an on-ramp about 5 minutes from my house where the car is rarely warmed up in time for. My car has always been like this, and (from what I've read) this is completely normal.

Just from what I'm reading, I don't see where you have a problem. If your car was warming up in less than a minute before, I'd say that was the abnormal condition.

When the car is "not fully warmed up" (1 needle below the middle), does your ECU let you run the full RPM range?

Same here in SCAL..... It takes much longer to warm up than my Miata and it stays one tick below the middle regardless of how long I drive it. If you are not getting heat from the heater, maybe there is something with your climate control.

 

[MLmotorsport]

If you are not getting heat from the heater, maybe there is something with your climate control.

Well I get heat... eventually and it's plenty warm - just takes a long time to start getting warm. If I can remember correctly it takes about 4-5 mins to start getting heat on a cold day.

 

[Viper Driver]

I'm reading up on threads here on Prime about the thermostat, and there are a few guys who have issues with their cars running cooler (just one or two ticks above the bottom) and that may be some of the threads you were reading. I suppose your situation is a "gray area" regarding the temperature, so only you can say if it's good or not. If your ECU lets you run all the way up to 8000 rpms, I'm guessing that it's happy with the engine temperature so you should be too.

Yeah, it takes about 4-5 minutes before I get any heat out of the vents as well. I know that because of how long my girlfriend complains about it on a cold day. :tongue:

 

[MLmotorsport]

I'm reading up on threads here on Prime about the thermostat, and there are a few guys who have issues with their cars running cooler (just one or two ticks above the bottom) and that may be some of the threads you were reading. I suppose your situation is a "gray area" regarding the temperature, so only you can say if it's good or not. If your ECU lets you run all the way up to 8000 rpms, I'm guessing that it's happy with the engine temperature so you should be too.

Well I guess I will stop worrying then. Maybe it was a needless replacement I had done - but it's one less thing that could be a problem anytime soon. Thanks for all the help guys!

Yeah, it takes about 4-5 minutes before I get any heat out of the vents as well. I know that because of how long my girlfriend complains about it on a cold day. :tongue:

You mean you don't warm the car up for her?!

Viper Driver - you going to be letting that '87 gray/gray go anytime soon? :wink:

 

[NSXTech]

I believe I know enough now to say your situation is totally normal. 4 or 5 mins is nothing for an NSX to warm up. With the t-stat closed during warm up, water circulation is limited so it takes a lot of low flow and convection to get hot water from the engine, thru the transverse tubes to the front of the car and then, the heater core. Your driving range coolant temps seems totally normal to me, as does your idle and warm up times.

side bar;
I know some of you drive Benz's and some of those models have (had) electric water heaters for instant heat before engine heat was available.

MB

 

[Viper Driver]

Glad to hear The Master (MB/NSXTech) chime in on this. I guess you can just think of it as preventative maintenance.

Viper Driver - you going to be letting that '87 gray/gray go anytime soon? :wink:

As Charlton Heston says....."You can pry it from my cold dead hands!" :tongue:

 

[Joe Gliksman]

FYI--I'm on my third thermostat. The original got stuck open, and it would take about 15 minutes of driving in Central FL to get warm enough for the needle to come off the bottom. The second one had the rubber seal on the thermostate break, so water was leaking by, and warm up was very slow. With a good new thermostat in my car, it takes about 5 minutes to warm up to a tick or two below the middle of the gauge--seems to run great.

Maybe yours is OK.

Joe

 

[MLmotorsport]

FYI--I'm on my third thermostat. The original got stuck open, and it would take about 15 minutes of driving in Central FL to get warm enough for the needle to come off the bottom. The second one had the rubber seal on the thermostate break, so water was leaking by, and warm up was very slow. With a good new thermostat in my car, it takes about 5 minutes to warm up to a tick or two below the middle of the gauge--seems to run great.

Maybe yours is OK.

Joe

WOW! Were those OEM Honda parts? Did they replace them free?

 

[Joe Gliksman]

Yes, all OEM parts. I have a 92, and the original lasted 6 or 7 years, the first replacement lasted maybe 5 or 6 years, so no free replacement. I did the work myself, and as I recall, the part is about $35 on-line, so no big deal.

 

[Tony Montoya]

The thermostat in my NSX is 14 years old and it still works. One tick below half and it takes a long time to warm up compared to other cars.

 

[ATERPAK]

I also changed mine after 14 years and the new one works the same as the old one. I also tested the old one using the test recommended in the manual and it tested as it should. So I really didn't need to change the thermostat. My car always runs just a tick below center unless I"m on the track and even there it rarely goes beyond 3/4. Finally, whenever, I MEAN WHENEVER you have work done by anyone, ALWAYS ASK FOR YOUR OLD PARTS BACK!!!!! This way you know they at least used your new part as you requested. Finally the only thing they could have done wrong on the thermostat is to put that little hole with it's little one way valve on the thremostat flange which should go on top during installation at the bottom. I'm not sure why it's really there but it's clearly marked on the thrermostat. I think (like most have said) all is fine. Go out and enjoy the car.

 

[MLmotorsport]

FYI--I'm on my third thermostat. The original got stuck open, and it would take about 15 minutes of driving in Central FL to get warm enough for the needle to come off the bottom. The second one had the rubber seal on the thermostate break, so water was leaking by, and warm up was very slow. With a good new thermostat in my car, it takes about 5 minutes to warm up to a tick or two below the middle of the gauge--seems to run great.

Maybe yours is OK.

Joe

Ok, I misunderstood - I thought you were saying that the first 2 thermostats you installed were bad right off. 6-7 years each isn't bad though.

I did open up my car on a long stretch of highway tonight and everything is running perfectly. The needle now sits between the middle temp tick and the tick below it, which is slightly warmer than it was with the old thermostat. Thanks for all of your help (and encouragement :wink: ). I'll be sure to ask for the old parts next time - it didn't even cross my mind yesterday.

 

[NSXTech]

Finally the only thing they could have done wrong on the thermostat is to put that little hole with it's little one way valve on the thremostat flange which should go on top during installation at the bottom. I'm not sure why it's really there but it's clearly marked on the thrermostat.

The hole you refer to is there so the system can bleed with the engine cold.
The 'one way valve' you recall is actually just a little pin that rattles loosely in the hole, its purpose being to keep the hole clean and therefore open. (the pin moves about randomly in reaction to flow)

In case anybody else cares, besides me and Al. :smile:

MB

 

[zanardi43]

ive never noticed before i read this post. i have a 99 and the temp runs at 1 notch below the middle during city driving, the only driving i have ever done since purchassing untill today. i just got home from a 3 hr. drive from vermont. on the way home i noticed that the temp dropped to the bottom notch during a long decline in top gear on about 5 occasions. the rest of the time it was at 1/4 to just below a half. when i got back into town the temp was at one notch below. is this the symptom of a bad thermostat? btw. it was @30 degrees and my heat takes forever to come on.

 

[Andrie Hartanto]

I don't know if it helps or not, but my 92 warms up really fast. That being said, my second thermostat only lasted 1 year.

Tom's 96 which I get to drive quite often warms up much slower. About the same way you desribed yours to be.

Just want to make a suggestion, thermostat is not an expensive part. In the future it is good to build a relationship with your local garage by buying inexpensive parts through them. Throw them a bone, so to speak.