bletzinger

took it to a honda dealer - blown head gasket, warped head. Thanks for you help.

FTF327

Hello, I am new here, I have an issue with my 2005 Civic Lx. Recently my car started to overheat while waitting in line at a construction zone:

One of the things I noticed is that now that spring is here this mornings are getting hotter for the car. It doesn't overheat on cooler days.
The temp does not go up immediately while in stop an go traffic, I have to wait for about two red lights to see the temp go up.
I replaced the thermostat, temp sensor (i wanted to get a cooling fan switch but they were out), and flushed the coolant.
When I park and check the fans they aren't moving, but when I turn on the A/C, the fans turn on just fine.

After I replaced the parts, I had later realized that this has happened before. When I first got the car a few years ago I had the exact same issue. After multiple times of the car getting too warm (I never let it get to the H) the head gasket finally blew and warped one of the heads.

Could this be an issue from the past? Or did something I replaced while troubleshooting the head gasket and go out again? I don't remember what get replaced the first time it happened unfortunately other than the gasket and thermostat.

I'll be buying the cooling fan switch tomorrow to see if that is the issue, but any recommendations are appreciated.

holmesnmanny

if the fan switch is bad the fans won't turn on. You need to check that both fans run when the fans turn on as the car is starting to overheat.

It's possible that the head(you only have one) is not warped by doing a compression test.

andrew lee

Hey fellas hope i could get some help. Got a 01 honda civic ex. Car starts heating up after about and hour of constant driving (freeway). New radiator and cap, thermostat, ac fan and might replace the coolant temp sensor. I dont think i have any leakes and dont think its the water pump. I purged the system when i replaced the radiator so dont think theres air bubbles in there. Is this normal to overheat that way? Anything helps.

MyAcc0rd

Nah, overheating isn't normal. Is your cooling fan working?

thisguyaves

Check the fan switch first and foremost. When it's overheating, the fan WILL be on if the switch is good.

Tim1959

I had exactly the same symptoms on my '02 Civic LX. The problems were caused by a warped cylinder head that resulted from overheating.
I had 0.006" shaved off the head, used an OEM head gasket set. All problems solved! :-)

dallascopes

Good afternoon everyone,
odd issue here...just purchased 2004 Civic EX coupe, auto, 1.7 motor, 137K miles...got home from making the purchase and radiator was spewing out the front of the grille. No overheat on the gauge, no indication of anything wrong until I was checking operation of more of the system, IE; a/c and heat, and found no heat. Got out, open the hood and that when the car pissed down my leg from the grille.
Long story short...radiator cracked under the fill neck, ran to parts store next morning, got new radiator, tsat and oring, coolant, and assorted items to effect the repair. (I have over 17yrs as a dealer tech, former honda/acura master tech, parts and service mgr, as well as another 20yrs as a capital equipment tech...just so you get an idea of who I am, and not some ig no ramous))
After completing the repair, I ran the engine until the tsat seemed open(upper and lower hoses hot), temp gauge never got to half way, fans never ran. fans will run with a/c, and will run when coolant switch connector is jumped.
Called it a day, went back to parts store next day, got new fan switch, installed it, and fans still will not come on. I figured that I had quite a bit of air in the system, even tho I have a fill funnel for the radiator neck, and jacked up the front of the car while running. ODB II indicates the car is overheating...200 - 215 degrees...temp gauge never goes to halfway...laser temp gun never shows the temp that high on any hose, switch body, or surface, coolant seems to boil at some point. We removed the tstat from the system, with the same results...no fans, high indicated temp...seems to boil the coolant...whats the next move??

toyomatt84

iTrader: (1)

Possibly a faulty coolant temperature sensor, if the headgasket isn't blown.

dallascopes

Toyomatt84,
I'll buy the idea that the coolant temp sensor is probably bad...but I haven't bought the idea that the head gasket is bad. No milky oil / no smoke on first start in am / no engine skip or misfire / no evidence of coolant burn on new spark plugs...
I am checking for combustion gas in the cooling system today, and will be greatly surprised if the reading is positive.
Will keep you posted.
Thanks for the reply.

dallascopes

Follow up to Odd Issue...
Tested for combustion gases this morning...several times...negative on the tests.
Using a digital thermometer, the temp gets above 195 and the fans never come on...keep in mind I can jump the connector on the fan switch and the fans run...and the fans run with a/c operating.
Question for the gurus...can the ect sensor cause the fans not to run? The temp gauge on the dash never gets above halfway.
Thanks,
DC

toyomatt84

iTrader: (1)

The temp gauge in the cluster shouldn't ever get above halfway, if the engine isn't overheating. The fans could easily not be triggered, if the ECT sensor is bad.

dallascopes

Follow up to odd issue...
I replaced yet another fan switch, and the also the ect sensor, and now have fan operation. Per the digital thermometer, the fans come on at about 190 and cut off at about 180.
This is currently happening with NO tstat in system, and the system only filled with water.
Now I want to button up this project, and install another tstat, and fill with fresh coolant.
The million dollar question;
How do I make sure I have bled all of the air out of the system, since there are no bleed screws(that I can find, either on the vehicle , or on google).
When I did the initial start up after radiator replacement, I loosened the ect sensor until coolant ran out, but that did not seem to work...what is the trick?
Thanks,
DC

Tim1959

Follow the procedure in the Factory Service Manual (FSM) TO THE LETTER.
There is no need to use a special burping funnel if you follow the Honda procedure.

I measure coolant temp with a scanner. The fans on my 02 Civic LX (D17A1) don't come on until the coolant temp reaches 204 degrees F at idle speed.
This is normal engine operation.
The fans are not activated by the ECT sensor. They are activated by the fan thermo-switch.

Bergquist10

Hey everyone! I have a 2005 Civic EX 1.7L and of course, having issues with it overheating.

I'm not sure how to go about fixing it, as I've replaced the thermostat, coolant temp sensor, engine temp sensor, pcv valve (which was likely not necessary), cooling fan, radiator cap, and the radiator but i'm still having these issues. Also, all the fuses seem to be fine as well. The radiator has coolant, there is no coolant leaking (it stays full, as well as the reservoir) I have 165,000 miles on the car now, and the timing chain/belt (not sure which) was done at 143,000, so I assume the waterpump was done as well. However the water pump is really used more when driving, right?
Anyway I don't have any reason to believe that the head gasket is bad, as the reservoir has no color/oil distortion, and the oil has no color/coolant distortion. And there is no white smoke coming out of the car.
The heater does blow cold(er) air when idle and the heat is on, could the heater core be causing the entire engine to overheat?

I am really looking for ideas. I've spent more money on this car than it is worth, and so far I'm pretty disappointed with this car.

Tim1959

-------------------------------
When you say "overheating" you must be more specific. Based on the dash gauge, or what?
Use a scanner to read the engine coolant temp while the engine is idling and the cooling fans are cycling on and off.
You MUST check the coolant level in the radiator filler neck when the car is COLD. It MUST be full ALL THE WAY TO THE TOP, otherwise, you have a leak somewhere.
The coolant level in the overflow MUST rise and fall with engine temp, otherwise, there is a leak in the cooling system somewhere. It could be an INTERNAL leak (even without white smoke).

Bergquist10

Overheating based on the dash gauge, yes.
I will get a hold of the temp scanner, and see if I can test it that way.
I just checked that this morning, and I feel like I put about 3/4 quart in there. That seemed fairly low, but I also noticed there was a little bit of pressure when I opened the cap too, after sitting all night? Should there be any pressure after that amount of time?
I didn't even think about it, however driving around last night, I didn't see the overflow adjusting at all. I think I did see it just staying a little over the "MAX" fill line. Is it supposed to fluctuate visibly a whole lot? Or just little bits at a time?

Tim1959

------------------
The scanner I use does a WHOLE LOT MORE than just read Engine Coolant Temp (ECT). A good scanner is essential for troubleshooting modern computerized motor vehicles today. I currently use an "OBDLink LX Bluetooth" device that transmits live on-board computer data from the cars computer to an App that runs on my smartphone (an Android device) via bluetooth. Info available at OBDLink® - OBD-II Diagnostic Scan Tools for Android, iOS, & Windows | OBDLink® | OBD Solutions.
There are MANY scanners available today from several tool manufacturers with a WIDE price range.
After sitting overnight, there should be NO PRESSURE behind the radiator cap because the cooling system was supposed to have just finished DRINKING coolant from the overflow tank. It sounds to me like you have combustion gas leaking into the cooling system from a warped cylinder head (been there, done that. VERY COMMON on these engines).
The difference in coolant level in the overflow should be AT LEAST 1.5" (from cold to hot). This is VERY hard to see on this car. I use a mirror & flashlight. (later model Civics have a better overflow design).
An overfilled overflow tank is a sign of an internal leak from a warped cylinder head. During engine cool down, the cooling system sucks air in through a combustion chamber instead of coolant from the overflow tank). Been there, done that! :-)
You might consider testing for combustion gas at the radiator filler neck. My car tested positive. At that point, I was convinced the cylinder head had to come off the engine. (laborious & expensive).
I had 0.006" milled off the head at a local machine shop and PRESTO, all the internal leaks were SEALED. The engine now runs LIKE NEW! :-) No more overheating or mysterious coolant loss, PLENTY of power, a SMOOTH idle, HIGH gas mileage. The engine now purrs like a kitten! :-)

Bergquist10

I actually use the Blue Driver with my android phone. And I read temps from that as well! I love it!

However, both this morning, and the morning before (When I filled the radiator) there was both a tiny little bit of pressure in it. So am not sure on that, or why would that would have pressure. Assumable that the heads are warped, but I don't think that they are...:
Here is the issue that I am coming across today. The overflow was just fine today, and looks like it was fluctuating (Maybe not 1.5") and it looks like everything was working properly. The temp would get up to 214 Degrees (F) and the fan would kick on, and cool it down to 207 degrees, the lower pipe and the upper pipe were both hot with coolant flowing through them. Well, just yesterday I drove it about 20 miles and parked the car, and the fan was kicking on constantly around 235. Drove back to my home and then the fan was kicking on at 214 again cooling it to 207. BUT GET THIS I turned on the AC today, which makes both fans go on, and it cooled it down to like... I think it was 196! But I know the AC doesn't always work like that, I've had it overheat to 250 because the AC was on full blast while I was driving then stopped.
The reason I cannot bring myself to believe that the head, or gasket is bad is because I am not loosing any coolant, not blowing any white smoke, and the oil doesn't have any funny colors. I have a buddy who has a block tester (That is waht he called it) and I plan to test that as soon as I can because as I said. I really don't think it is the head.

I just want to say however, I am super stoked about the answers everyone has given me. I have been relentlessly looking at solutions for this car, and all of this helps so much! THANK YOU!

Tim1959

----------------------
235 degrees F sounds too high to me for coolant temp. That's MUCH higher than boiling (212).
With 100 degree (F) ambient temp, (Las Vegas area) my cooling system fan turns on at 203 (F). The coolant temp then fluctuates between 196 and 205 (F) while the fans are cycling on and off.

Tim1959

Following is a useful summary of my recent experience with a 2002 Honda Civic LX, auto trans, 1.7-liter engine with 185,000 miles:

Typical Symptoms:

1. Engine overheating (as indicated by dash gauge).

2. Mysterious loss of coolant from the radiator (with no visible external leaks).

3. Overfilled coolant reservoir.

4. A stream of small bubbles in the coolant reservoir and/or radiator (with the engine running).

5. Excess pressure inside coolant reservoir.

6. Exhaust gas inside the radiator filler neck area (cooling system fails block test).

7. Gurgling sound from the cooling system immediately after shutting down a warm engine.

8. Small amounts of engine oil in the coolant.

9. Coolant mixing with engine oil (milkshake-like appearance under oil cap on valve cover).

Likely Causes:

1. WARPED CYLINDER HEAD that resulted from engine overheating, and/or

2. Blown head gasket.

Allowing combustion chamber gasses to leak into the cooling system (creating excess pressure in the coolant reservoir) and/or coolant to leak into the combustion chambers and get vaporized (lost out the exhaust pipe).

Recommended Solutions for success:

1. Use OEM (Honda) parts exclusively

2. Follow the OEM (Honda) service manual TO THE LETTER.

Happy Wrenching! :-)

mcardlepm

OK - I have a theory, and several tips, based on my experience. The odd 2001-2005 "no oil in coolant, no coolant in oil, no radiator pressure drop, no coolant in cylinders, no white smoke, no bubbles in radiator" but overflowing coolant bottle and occasional inconsistent overheat, is of course head gasket as everyone eventually finds.

However, this leak is so inconsistent and minor, and based on "mechanics feel" replacing the head bolts, I think the root cause is head bolt washers that are not of sufficient hardness, or they fatigue easily. After thousands of heat/cool cycles they compress and the bolt heads, when cool, no longer contact the head. This allows head flex under load, allowing hot exhaust gas to occasionally escape past the gasket, eating away its plastic coating, allowing relatively small (but growing) amounts of exhaust gas into the water jacket. Totally unscientific: the old washers are visibly thinner than their replacements, I didn't even need to mic them.

If you're a perfectionist, are doing a "real" restoration, you may hate my tips. Hate away! It's your right! But if you're budget-conscious, don't have a fully equipped shop, or are looking to get back on the road while not making any "real" compromises, at least consider what I did successfully.

All the procedures for head work have you remove all the parts associated with the timing belt, since only a fool would do head work without doing the timing belt, water pump and tensioner while you're at it, right? But what if all that stuff was recently replaced? For starters, this means leave the alternator, harmonic balancer and motor mount alone, hours saved, IF ONLY you could figure out a way to not screw up the cam timing. Again, I know there are some who'll take issue with what I did, but it worked like a charm, and worst case (assuming you check the valve timing before rotating anything) you just end up doing the work you tried to avoid. HERE GOES. Align the engine at cylinder 1 TDC. Using several zip-ties, zip tie the timing belt SUPER TIGHT to the cam sprocket all around the 180 degree contact area. Also match-mark the sprocket and belt. Using a bungie at the very top ("UP"), support the sprocket so when the bolt is removed, it does not drop at all, not even a split second, and maintains tension on the belt, tensioner and crank; I had a longish one I wrapped around the hood hinge and secured on a brake line. Also zip-tie the bungie to the cam sprocket. When you remove the cam bolt, gently move the sprocket to the rear enough for clearance; it helps to have an assistant just in case. When putting the head back, you simply have to rotate its shaft to the TDC-1 position on the bench, put the head in place on the block, and the cam sprocket should be pre-aligned if you've been careful. Replace the camshaft sprocket bolt making sure the pin aligns and NOT forcing anything as you tighten. Confirm by referencing the crankshaft/balancer TDC-1 white mark before installing the head bolts and AGAIN before rotating the crankshaft at all. Then, of course, install the head bolts in the proper torque sequence, remove the zip ties and bungie, rotate the crank knowing you stop at the slightest resistance, check the marks, and adjust the valve lash. Zip-ties and the bungie saved me boocoo unnecessary work.

Also, it is WAY easier (due to corroded bolts, nuts, and horrible fastener accessibility on the intake manifold), to remove the head, water outlet, fuel rail and intake/throttle body as a unit, and disassemble on the bench. Once out, those inaccessible intake studs are easy - and only remove the (5) attaching the assembly to the head, leave the fuel rail and throttle body attached to the plenum. Sure it's a little heavier, bulkier and unwieldy, but worth it. And you never disturb throttle-body and intake manifold gaskets, or run the risk of cracking a fuel injector, either. More time and expense saved.

When faced with head gasket replacement on a 200k mile car that's otherwise pristine, of course you're going to do it. And of course you need a nice flat head surface, and of course you'd be an idiot to not lap the valves and replace the seals too. Local machine shops catering mostly to American classic/muscle cars "weren't sure" if a Civic head would fit into their planing machine - if so, it would be $100. Valve lapping and seals - who know$, a couple of responses were so patronizing it was like they didn't want my business and refused an estimate without seeing it (meaning an hour round trip on my part), though "ball park $300-$500." When I found reman heads on eBay in the under $300 range, that's what I did, meaning zero shop downtime. And I'm getting a shop that specializes. A no-brainer.

Tim1959

--------------------------------------
When you say, "I think the root cause is head bolt washers that are not of sufficient hardness..."
Are you talking OEM or aftermarket parts?

mcardlepm

I have no way to know with mine, though there are extensive repair records from previous owners going back to the dealership purchase and including every oil change (and 3 water pumps in 2 years) but nothing head related. Also I have no way to know with all the forums’ cases with precisely the symptoms I described, but OEM is the logical assumption, at least the ones installed at the factory. It seems more realistic than bolt stretching/fatigue since none snapped on removal, plus the washers are a “normal” bright washer color, not black like the bolts OR the black washers on the Mahle set I replaced them with. I kept my old bolts and washers for analysis, just in case.

NotBruce

Thanks for the detailed reply.
In the end, my nephew did the rebuild for me (he builds performance engines, so I trust him )
The car had overheated at some time in the past (previous owner, not me), so the head was ever so slightly warped - not enough to leak visibly, or mix water and oil, so really difficult to diagnose without a strip-down (common D16 issue, I believe). Head was skimmed, head gasket replaced, new stretch bolts, new thermostat (pump was fine), new radiator (the old one was full of gunk - someone used a biscuit maybe, or rad sealer? Who knows...) However, the kicker was that the overheating issue masked the fact that the cam sensor was screwed. Have now replaced that too and it's running like a dream. I bought the Civic as a 'fill-in' while I was trying to source a gearbox for another car (Suzuki Wagon R+), and then my fella gave me his old one (Mitsubishi ASX), so I now have 3 cars... Will probably sell the Civic now (and make a loss overall), but will wait until I get my Suzuki inspected to make the decision - if it (the Suzuki) fails, then that'll go and I'll keep the Civic. I need a rat-car for kayaking (don't want to scratch up the ASX loading and unloading boats, plus it's a bit tall to make doing that easy), so the Civic will do for that.

This slight warp after an overheat is a really tricky one to diagnose, and so many garages just won't invest the time and effort. I know a head skim and head gasket replacement isn't necessarily a cheap job, but in the long run it works out a heck of a lot cheaper than going back to the garage time and again while they try to figure it out, and do a load of unnecessary work in the meantime. Although it goes against my principle of 'look for the simple fixes first', I'd suggest that as the first thing to try now when faced with the symptoms described.