zena01

I need help. My Honda is getting on in years and I’m trying to keep it alive. Back in September, the heat stopped working. Replaced thermostat, fixed the overheating but now only have heat when at higher rpms. Then a check engine light came on, P0401, EGR valve code. Engine is running a little tougher and gas mileage is about a quarter to third lower than normal. Problem is, there is no EGR valve on this engine. Any suggestions? My husband can do some things himself, so trying to do the easy stuff before we declare the car a loss T.T

ezone

So it has been overheated?Temp gauge needle stays in the middle again?
Radiator is probably low or the heater core has air trapped in it. Fill the radiator and "burp" the system of air. Radiator needs to stay completely full under all conditions. Reservoir should be half full (to the max line)

Look for coolant leaks, find why the radiator went low again (or if you didn't get it completely full).

And know these engines are well known for blowing the head gasket....which at first results in low coolant level in the radiator (while the reservoir gains liquid), poor heat at low RPM, mysterious overheating (result of slightly low level in the radiator). This forum is full of threads about it. Search for "overheat" and "no heat" and "head gasket"...and read the overheating common causes sticky thread.

If it's stupid cold in your area, the heater just might not be able to give much heat at low rpm.

Make sure the water valve is being opened and closed when the temp control is moved between max hot and max cold
Code readers aren't always 100% reliable. Try checking codes with a few different units and see if they give a code that is more realistic.

zena01

[QUOTE=ezone;4737892]So it has been overheated?

It did but was shut off immediately as it rose over half. We live in ND so it’s been too cold to investigate too deeply. I’ve been reading the forums and I am inclined to think head gasket as well, which will have to wait until spring since we don’t have a heated garage. I have been maintaining the coolant level but after the new code, it’s been sitting for now.