98 Honda Accord EX 4 cylinder overheats intermittently for about 3 months now.
Had the thermostat replaced the first time it started over heating and that fixed it for a while.
I replaced the thermostat with a fail safe one.
Then it started overheating again only when i was in heavy traffic or when i was idling, and it seemed to be low on coolant so I put more in it and got the air out of the system and it seemed to be ok, but I was moving so I took it into the shop anyways.
They pressure tested the system, replaced the thermostat again with a factory one, AND the radiator cap.
They said that everything was fine and that it wasn't overheating during idle. NOW its overheating again when I idle or am in heavy traffic and it seemed to be low on coolant again, so I did the same thing and got the air out of the system by running the car with the radiator cap off an pouring coolant in until there weren't anymore air bubbles, but there is coolant spewing out of the radiator cap even when the cap is on, again only when I get home and have been driving in traffic.
The coolant that I have been using and that the system is completely full with now is the Autozone 50/50 brand.
It was mixed before but after so many services its basically all the Autozone stuff in there now.
I have checked the oil and it is not milky or anything and seems normal.

 

At some point you are going to need to watch the fans and see if they arent running as it starts to overheat. Report back if they dont. They should both run simultaneously.

 

Is it dumping coolant out of the overflow canister? It may not be allowing the coolant to go back in as the engine cools off. if fans are working, might want to do compression test, may be a small head gasket leak.

 

The fans I am going to have to double check, but I am pretty sure I have seen them come on even as the temperature rises.
It is not spilling out of the overflow canister no. It does seem to properly pour coolant into the overflow if there is too much in the system, although that begs the question of why there would be air in the line.
Even this morning when I drove to work, about 40 mi., 50 min., i opened the hood and the radiator cap is seeping a little bit, and I bet when I drive it home in the Texas heat along with the traffic that it will be spewing out of the radiator cap again.
When I went to OReily yesterday to see about a new rad. cap, the guy said it was probably a different issue and that it wasn't the cap since it was replaced so recently.
He also said that it could be a head gasket issue, but again I check the oil and it seems normal and wouldn't there be visible coolant in the oil if it were a head gasket?
Some other info about the car, it has 197k miles on it, the xmission was rebuilt at about 100k, and the water pump and timing belt has been replaced too, I think at around 120k.
So needless to say I am at a complete loss. I guess I could go ahead and drop the 10 bucks on a new rad cap just to completely rule that out.

 

If you have replaced the t-stat recently and the car was functioning normally before that, it is probably the head gasket. They are not that bad really. I can have a Honda head off in about 25min with the right tools.

Getting it all back on takes a bit more time.

I have only had oil and coolant mix with one headgasket failure on my Hondas and that was a massive leak.

Most of have just overheated occasionally, ate coolant and pushed it into the overflow. Sometimes green spark plugs and sometimes sweet white smoke out of the exhaust...

If the fans are working and coolant is circulating I am leaning towards that being the issue.

 

What happens, is that a little combustion gas is getting into the coolant(You can actually test for this gas in the coolant if you want) and that does two things, first it makes it really hot, and second, it over pressurizes it. Normally it will fill the overflow tank, and then dump out of the overflow spout. I would recommend you get the head machined before re installing it. If this proves to be the issue.

One other thing, and i dont normally recommend this, unless the car is a POS and youre only looking to spend the least amount possible to get it going. They sell the fix in a bottle, and for small leaks...which it sounds like you have...if you follow the directions, they normally work pretty good. I recommended this to a girl with a 97 ex and it fixed it, and its been driving normally for 18 months now. Borrowed time for sure, but it cost her $25.

 

I second having the head milled to ensure that it isn't warped, or checking it to make sure it is within spec. I've actually bought a few Hondas that way. Somebody does the headgasket but doesn't get it checked, replaces HG... HG blows 3 months later- I buy on the cheeeaaaap...

Flip for quick profit.

 

First of all thank you all for your input, I greatly appreciate it as I am on a budget and need to consider all my options.

While the car is not necessarily a POS, the cost of a gasket job would be more expensive than the car cost in the first place, and with almost 200k miles on it, I'm not sure that a 1200 gasket fix, not to mention however much it would cost to get the head milled, not sure what that even is but it sounds pricey, I'm not sure I want to make the investment in a car I probably won't have too much longer. Plus goodness knows even if I did do all that, something else would go wrong and it would be back in the shop.
However I do want to drive it into the ground so I am interested in this fix in a bottle. If I just went to Oreily or Autozone would they know what I'm talking about?

Lets just say I did do the full fix getting the head milled and a gasket service, should I go to a neighborhood shop, or a Honda Service center? Both are near my house thankfully.

 

DO NOT buy that crap in the bottle. It's worse than useless.

Considering that Honda charges about $900 for a timing belt package, $1200 is about right. Speaking of which, if you have the headgasket done you need to go ahead and have the timing belt package (belt, tensioner, and waterpump) done too as they have to take the timing belt off to get the head off.

Usually the independent shops are cheaper but, the best place to go is an independent shop that specializes in 1 or 2 makes, Honda in this case.

 

Is it really too much to ask for you to see if the fans come on before you throw away a potentially perfectly fine car?

I suppose if you want to just assume the worst, that's your choice, instead of actually troubleshooting the issue. (eg. compression test etc etc)

I didn't realize looking to see if the fans are turning on when the car is overheating is a lot of hard work.

 

holmesnmanny Sssshhhhh!These are the Hondas I pick up for cheap on Craigslist, mill the head and drop in a new gasket and flip for $1250 worth of profit....

I thought he had already checked the fans? The bottle.... face palm. I usually see remnants of that crap when I do HGs and have to flush the cooling system of that junk.

 

Got it, NO on the bottle crap.

Yea look I apologize, the thing is is that right now the car is NOT currently overheating, I'm just having the issue with coolant spewing out of the rad cap.
And yes, when the car was overheating last Fri. I had pulled off the road so as to let the car cool, and I let it idle and get hot and overheat and watched for the fans to come on and they did.
The reason I am saying I want to double check is because when I did that I was frustrated, seating in the Texas heat, wanting to get home for the three day weekend, etc.
So while I'm pretty sure I checked for this when I had pulled off I am simply not 100 percent sure of myself and would want to check again just to make sure that they do come on when the car starts to overheat.

I will be taking it in for a compression test this weekend.

 

Mine was overheating as well, same symptoms. I replaced the thermostat, water pump, fans and it was a bad radiator that looked perfectly good from the outside.

 

Are you sure the rad cap is good - check both seals on the cap. Next is there a crack in the top part of the radiator?

 

Update: Took it in to the honda dealership, they said it was the water pump leaking, so they replaced that and did the whole timing belt package, $800.

Didn't fix the problem, still had fluid spewing out of the cap. Took it to a coworkers trusted place, has all five starts and everything, they said they saw air bubbles coming out of the radiator so they are certain its the head gasket.

Took it back to the honda place after getting chippy about the whole situation and they said they pressure tested it again and still couldn't find anything and don't think it's the head, BUT they said that I don't have a stock radiator on there and so the stock cap that's on there has the wrong pressure rating and that is why it's spewing.

Talked to my boss about all this, he's gone through several cars, he said that the head was the first thing that came to his mind, but that there could also be a block in the radiator as well. But would that explain the air coming from the radiator?

 

All you have to do is compression test as i said before to make sure the head isn't warped.

If it tests good you can get a Denso radiator and radiator cap from rockauto for around $70 that will probably outlive that car.