90_civic_Si

I have a 97 Acura EL and am having some heating problems. I replaced the thermostat with an oem honda t-stat a few months ago. Now that it's getting cold out I notice that I don't have any heat, not really even luke warm.

I tried flushing the heater core and I did have some rock like coolant chunks blow out with compressed air so that was good. So I sealed everything back up and bled the system in the shop and had good heat. Both hoses going in and out of the heater core were hot, slight difference in temp but still close. So the fan came on and I shut the car down and waited a bit for it to cool down and topped off the rad and tank.

I leave the shop and drive home and by the time I got home I had no heat again and the heater hose from the firewall to the coolant pipe/t-stat housing is somewhat cold compared to the boiling hot inlet one. So I probably have to replace the heater core or get some cleaner and flush it out with that before I pull the dash out.

My question is about the temp gauge though. It only comes up maybe 35% not the full half way. It has been like this since I bought the car 4 months ago. That's why I replaced the t-stat in the first place but the gauge still didn't read half way. Is this normal? If I had a bad t-stat the gauge usaully doesn't move off cold or goes way past half not just stay between cold and half?

wheelmanbg

I'm not familiar with your Acura but on my Civic, the temp gauge NEVER goes up to halfway. It only goes up about a third of the way

Targa250R

Before pulling the heater core, I'd suggest checking the water valve to make sure it is operating properly.

It sounds like your temperature is spot-on. Under normal operation, the water temperature gauge should read slightly over 1/3 of the way up the scale. I have never seen a Honda temp gauge register at 1/2 or higher unless there is a problem.

90_civic_Si

The heater valve is working properly, and I didn't know that about the temp gauge. Everyone always says temp gauge should read half. If my temp gauge is ready right then my heater core is plugged.

I'm gonna try to flush it out first with some sort of chemical and if that doesn't help I'll have to replace the heater core. It sucks because I bought this just as a winter car and it doesn't have heat!!!

wheelmanbg

better bundle up lol

Seriously though, I'm pretty sure replacing the heater core will fix your issue. I've never had to do that but pulling the dash is a PITA

Good luck

90_civic_Si

Well I tried flushing the heater core again this morning and still no luck. What I did notice though and I did notice this last time I flushed the system is that I cannot get all the air out.

I will let the car cool down and then start it and inside the car I can here water moving behind the dash and then it goes away. That to me is air bubbles still in the system. So I jacked the front of the car up again and popped the rad cap and bled the thing with the rpm at like 1500, all kinds of little bubbles that don't stop until the fan comes on.

I let it cool down and topped it off. Start the car again and this time I ran it at 1500rpm until the fan came on at least 3 times. Everytime before the fan comes on and the coolant drops I have this frenzy of little bubbles. Now the funny thing is is that both heater hoses are hot and I have heat, not heat like eye bleeding heat but better than nothing. Then I go for a drive and the heat is gone after a few minutes.

So now is the heater core so plugged that I cannot bleed the system or is my headgasket the problem? To me a bad headgasket makes the car smoke, burn coolant/oil or run funny. I don't have any of these problems with my car. It idles perfect and the temp gauge goes up and stays where it should even with the running at idle for hours.

90_civic_Si

Before I tear the dash out I want to make sure it's not something stupid like a bad t-stat. I already replaced it a few months ago with oem honda parts. So i start my car with the car starter and run it for about 10 mins, go to tim hortons(coffee) and let it run, then I drive to work about 10 min. So now my car has been running and driving for a good 30 min. I have no heat, pop the hood and the lower rad hose is still cold.

Is the t-stat stuck open or what? The temp gauge inside is reading about half way.

canadaek

try a new rad cap i had a accord do this also.

90_civic_Si

hey yeah I never though of that.

90_civic_Si

replaced rad cap and still same thing. The thing I don't get is that it takes so long for the lower rad hose to even start to get warm. Like 40 minutes or so. When cold and the rad cap is off and engine running I don't see any movement in the coolant. Once it finally warms up by me holding the throttle cable it starts to flow but by this time the t-stat is open and the lower hose is hot and I have some heat.

A few weeks ago I could hear this high pitched squeal from my waterpump/alternator area. It happened a few times and then went away. What happens if the waterpump breaks, this would cause the very slow lower rad hose heating up but wouldn't the waterpump continue to make noise?

canadaek

if the impeler fell off it might not make noise anymore ? have you had it tested for c02 in the rad ?

wheelmanbg

how old are your water pump and timing belt?

When my water pump was going out, it only made noise intermittently and was not leaking coolant.

Former User

Never ending gas bubbles in the coolant sure sounds like a blown head gasket.

90_civic_Si

Oh fure sure but what are the systoms of a bad headgasket?? Rough idle, burning coolant/oil, overheating? I have none of these problems and I can let my car idle for hours in one spot and the temp gauge reads normal and the engine never overheats.

After flushing the entire system trying to bleed it I have some heat now but I still start the car in the morning and car here bubbles moving through the heater core. Why the hell can't I bleed this thing!!