Overheating and funny idle need help

My girlfriends car is a 1987 honda accord and lately its in trouble. Have been having to add about a gallon or more water a day.

I am new to working anything but chevy pickups. I am going to replace the thermostat and was wondering if someone could give me a quick description of how to do it and where the thermostat is on it.

Also the car has a very erratic idle at times. It mostly occurs when the car is idling in park the idle will go up and down constantly. It doesnt rev up to high just extremely annoying any help would be greatly appreciated.

Thanks in advance.


Bryan Miller

You keep having to add water into the system? Are you sure it isn't leaking anywhere? Is the exhaust smoking at all?
When was the last tune up on the car? Could be a bad iac, or maybe egr valve. Not really sure about that generation car.

Have not found any leaks when its stopped and she says theres never a puddle under the car. And there is no smoke from the exhaust. Her uncle supposedly had it tuned up about 5 months ago.

Well, start the car up, and check under the hood. If there is a small pinhole leak somewhere, once the engine reaches normal temp, you'll see it gushing out. Have you pulled out the plugs and checked them? But yeah, I'd suggest checking the therm. Can't remember if the heater core is before or after it, but you could also try turning the heat on and seeing if its blowing hot or cold, and then diagnosing it off of that.

follow the lower rad hose to engine block, the t-stat is located there.

the idle problem is due to low coolant.

I would do a compression test & pressure test on the cooling system. If your adding a gallon a day it's going some where, leaking or burning. Check the left side(driver side) of engine of signs of coolant leaking. The water pump is located under the timing cover and driven by the timing belt. If the pump is leaking REPLACE the timing belt at the same time.

A wet timing belt will break and that could cost you a new engine.

jackasssi, are you sure about that? i just did a thermostat change on my 86 accord and the thermostat was located off of the upper radiator hose.

not 100% sure, some are on the lower some are on the upper. I usually figure it out by actually seeing the engine.

Well good news. Her family found out the car is havin trouble and also that I was gonna fix it and they decided she should drive home and let them fix it. They dont like me to much. lol But thats ok with me saves me the time and money that I would have had to put in it. Thanks for all the help. Its awesome how everyone helps out each other. Just letting you know that it is greatly appreciated