JackImpact

Have the setting set on its hottest. Absolutely no heat while driving or idling. I live in Florida, so it could be worse, but I'd like it to work.

No idea, hopefully its just a fuse or something stupid like that.

Fan adjusts speed properly and where I want the air to go, but it only does the coldest air.

Help =[ Helps me defog my windows from the humidity. Also If I move back north I will need it lol

Thanks guys!

TinkerinWstuff

having the same problem.

verified that the heater control valve is functioning properly and engine temp gauge reads normal.

my problem is intermittent. Normally the heat flows fine. When it fails to work properly, it will eventually come on and blow hot air like someone flipped a switch.

Occurred four times in the last two months. Most recently was yesterday morning and this afternoon.

210k miles, 2002 DX, engine running great and pulling 38mpg.

Matt_75

How's the reserve/overflow tank coolant level? Any over heating? Is the radiator full to the top? Any coolant on the engine?

mikey1

you have air pockets in your cooling system....

these air pockets will go to your heater core....

when you have air instead of coolant in the heater core, you will have no heat,

you might have a blown head gasket

TinkerinWstuff

yes, it's looking like the head gasket. Checked a few things this morning and then did a compression test.

#3 is only 125lbs while the rest are pulling 165 (cold).

pretty surprising the thing would continue to run so well and the problem so intermittent.

all well.... time to get busy.

TinkerinWstuff

Well, gonna have to put a few miles on to be sure but it appears my problem was likely a radiator cap.

New cap and things appear to be workin correctly. The low cylinder comes up and is well within 10% of the rest when tested warm. The traces of water in the oil when i first checked may have just been condensation. Will drive the hell out of it this week and see how it goes.

Matt_75

Wishful thinking. It'll be back. Don't worry.

I didn't even bother with a compression check. Reserve tank spewed coolant all over the trans and was full to the top. When I opened the rad cap, a burst of air came out. I knew right then what it was. #3 cylinder is the one that leaked on me.

You can see in the picture below the discoloration in #3 cylinder and even a little in #4. The below picture was taken fresh of the block. You can see where the HG coating dissolved and allowed the water jacket and cylinder pressure to mix.

BTW how are the levels I asked about in my first post here?

TinkerinWstuff

Res was full but never overflowed. Would not suck fluid back in on cool down. Coolant never pressurized from combustion gas leakage that I can tell.

New rad cap and multiple heat cycles have it operating properly again and all air out of the cooling system now. Will need a couple butt-cold mornings and a few drives to be conclusive.

Matt_75

Res was full to the top or full to the max line? Was the rad a little empty?

Matt_75

BTW, it's ok to be in denial. Many have passed through these forums with the same symptoms and have replaced the rad cap, rad and water pump. In the end it was always the HG.

TinkerinWstuff

Time will tell. Drove 2 hours on four trips today and it's working flawless so far. So it doesn't make sense to throw a pile of money at it at this point.

Weather has been mild. I'll feel better about it if it performs correctly on the next 15deg morning.

Matt_75

Well, good luck with it. If it spews coolant out the reserve tank and rad is partially empty, you know where you stand. If it does the a fore mentioned and overheats, you know where you stand.

TinkerinWstuff

I used to do head gaskets for a living back in high school. Hopefully I won't need to do another. Ford Escorts of the '80s were famous for blowing HGs around 100k and made a good living for a kid in the early 90s. Thus I'm quite familiar with the symptoms.

Matt_75

These civics are quite famous for blowing them too at a wide range of mileages, age and with out most of the symptoms you probably think are typical in your experience. There are about a gazillion threads on them all over the internet.

Good luck with your problem. Maybe you'll be the exception in fixing it with a radiator cap.

TinkerinWstuff

I hadn't realized that Honda engineered changes to the water cooled, reciprocating, internal combustion engine that affected the physics of differential pressures? Back at ya

You got hands on that F-22 in your photo? I used to be an F-15 crew chief at Langley. Our squadron was slated to get the 22 but kept getting delayed and didn't happen while I was in.

Another 130 miles today without issue.

TinkerinWstuff

Just following up for folks....

Almost two weeks and nearly 1000 miles. Working perfectly. I'm quite happy it was an $8 fix and not anything more painful.