Hang in with me here. I need to give some background on the issue(s). I've taken it to 5 different shops, and have gotten conflicting reports, and no solutions. The car has 170k miles.
The first problem I experienced with this car was overheating while not moving at 40mph or above. When I would stop at a light, or in traffic, the car would get hot. If I was moving at a decent speed, the temperature would come back under control.
The first time I brought it in, NTB couldn't really see any problem, so they reccommended a coolant flush, thermostat and radiator cap replacement. I did that, and it seemed to deal with the issue for a few weeks. After that, it slowly started acting the same way.
At that point, I brought the car to a Honda dealer, and was told that the head gasket needed to be replaced. Looking for a second opinion, I brought it to a small shop run by a buddy I trust to tell me the truth, and he could not find any problem with the head gasket, and said the symptoms I described (even though he didn't see them) were inconsistent with a head gasket problem, so he replaced the thermostat again with an OEM part, and again, that dealt with the overheating for a while.
The problem started slowly coming back, and it also started running slightly rough when I would first start it up. After 5 seconds of idling, the car would run smooth. All of a sudden one morning, the car ran so rough at startup that it would not stay running so I had it towed to another NTB. That shop also told me that the head gasket needed to be replaced, so again, I brought it to my buddy, and as soon as he tried to start it, it behaved nomally. It started normally, and it would not overheat, even after hours of operation.
I left the country for a few weeks at that point, and had my Buddy keep an eye on it. He ran more tests, and found an error code indicating that the Electronic Load Detector was faulty. He replaced it, and didn't have any problems with the car while I was gone. I picked the car up two days ago, and it ran fine, with the exception of again running slightly rough when I would start it, but again it was for only 5 seconds.
This morning, the car would not start. I towed it to a Goodyear, and upon arrival, it started and ran just fine. They don't see any issues with the head gasket, and are going to keep it overnight to see if they can duplicate the problem tomorrow.
So at this point, I've had 5 shops look at it. Two of them replaced the thermostat. Two of them said the head gasket needed to be replaced. Two of them said they don't see any problem. That seems like fuzzy math, but my Buddy replaced the thermostat even though he didn't see any problems first-hand.
Any ideas?
This Question has been solved and asker verified All Experts Exchange premium technology solutions are available to subscription members.
Experts Exchange has been collecting answers to technology questions since 1996…3 million and counting! If you have a question, chances are we already have your answer.
If you can't find the exact answer you're looking for, ask our exclusive community of 50,000 experts. You’ll get a personalized answer from a trusted professional.
Thousands of free tech tips, tricks, how-to’s and tutorials are available in our peer reviewed articles section. See for yourself how smart our experts are, no login required.
Save solutions to your questions, answers you’ve discovered through searching plus helpful articles in your personal knowledgebase for easy future access.
Access the answers to your technology questions today.
30-day free trial. Register in 60 seconds.
Members of the expert community talk about why the experience at Experts Exchange is different than what you will find anywhere else.
Try it out and discover for yourself.
30-day free trial. Register in 60 seconds.
Join the community of experts here and help other tech pros by answering question in your area of expertise. You can earn FREE access to all Experts Exchange's premium features and resources.
The shops that disagree with the headgasket diagnosis site the lack of those symptoms that you describe (no oil in coolant, no steam from tailpipe). They also say that it is maintaining compression, and one of them ran a combustion leak test, and it passed.
I think its important to note that for a long time, the only issue was the overheating, and that the issue with running rough is a VERY recent development.
Have you had a tuneup performed? Modern computerized ignition systems can mask problems for a long time because of their ability to adjust to changing conditions. I'd have all your ignition components checked - sparkplugs and plug wires checked and/or replaced, etc. Also have your airfilter checked.
After doing the coolant flush did you bleed all the air out of the cooling system? On newer vehicles, I would consider 2001 Honda newer, all the air needs to be bleed out in order for it cool properly. There's usually a bleeder valve to bleed the air. Try looking in a repair manual like Chilton to see where the bleeder valve is. It doesn't hurt to try it since it's free. :-)
"overheating while not moving at 40mph or above. When I would stop at a light, or in traffic, the car would get hot. If I was moving at a decent speed, the temperature would come back under control."
Thermostats can often stick & cause overheating, even new ones.
If your not in a cold place remove it & see if your overheating stops.
If not, then you can troubleshoot other possible causes.
By process of elimination is the only way to diagnose intermittent problems like you describe.
One possibility is a water pump problem. Either the drive belt is slipping silently and it doesn't circulate the coolant efficiently enough, or it has a leaking axle seal and takes in air that way when running, which also would impair pump action. Did you have the cooling system pressure-tested?
/RID
Dirty Block... no water flow through the block for a long period of drive 30+ mins at a time can casue these problems and wont show up. I had a customer with the same issue. We tried everything. It got to the point were we popped the freeze plugs out and flushed the block the correct way and it started working fine and no overheating problems. Check into it. Very cheap to try out.
Try this first, it should be the first step in your process of elimination to diagnose intermittent problems like you describe :
http://autorepair.about.co
More info:
http://www.google.com/sear
& then read my previous post:
05/14/09 05:37 PM, ID: 24382703
The overheating could be caused by the engine running lean, possibly due to a tired fuel pump or a long term buildup of deposits in the injectors. have your Air/Fuel ratio checked. Its a fairly common issue in high mileage cars.
A quick probing for HC (unburnt fuel) in the coolant would determine if the headgasket is on the way out. Personally, I would trust a Toyota dealers diagnostic equipment over that of a garage going by observation of oil and exhaust gas. On a cat-equipped car you'd need a far amount of coolant to make any discernable steam, and an overheating engine can give even compression between cylineders even if the head gasket is not sealing fully.
with regards to your overheating problem, a defective thermoswitch might also cause overheating. Most cars have thermoswitches connected to the coolant lines that only activates radiator fans at certain temperatures.
When these thermoswitches gets clogged-up or damaged your radiator fan would no longer work and might cause a similar scenario to yours where your car would overheat at low speeds or when not moving. At high speeds, the radiator is cooled down by the air passing through it, thence would help it cool down. Have this look at and replaced if you need to.
Your head gasket may blow-up or damaged when you drive your car while it's overheating. Worse is, you your head might get warped by the heat. You can actually check this yourself initially by checking for oil/water mixture in your engine oil by checking your dipstick. When your head gasket is already worn out one result could be is that water might enter into your lubrication system. This would make your engine oil look like a choco drink (light brown) in color.
To confirm if you're engine needs a head work or rebuilding, you might have a compression or leak down test conducted.
But the good things about the Honda's are the "Engine Swaps" :). You can have a higher performance engine and bolt it right into your honda with less work than any other car (I think) ;)
It sounds like its for sure NOT the headgasket. If you had a compression test done and it came back fine, the gasket is working. If the gasket were "blown" compression would be down in at least 1 cylinder.
I think your problem is probably a combination of things. First off your car overheating. I'd do what Michael-Best suggested and remove the thermostat. This will cause all the coolant to flow constantly. If the overheating issue stops you know the problem is realated to thermostat. If the overheating issue continue's its gota be something else. Probably one of the many possible causes listed from everyone else (dirty block, air in coolant, etc.).
You may want to have the valves checked, especially if its never been done or was done a while ago with a motor on that many miles. Usually the valves are loose however yours may be tight. This would cause the rough idle and could also play a part in the over heating (tight valvles run hotter).
2 possible causes 1-Headgasket(may be minor leak)2-Plugged radiator(to check warm car up then disconnect negative battery lead then feel radiator fins if there are alot of cool spots then your rad is plugged and most likely needs replacement)
Note:While car is warming up make sure cooling fan is coming on.
Well if I was having overheating problems. I would remove the thermostat (temporally A week or so) see how the system does with no thermostat at all. With the car cold not been ruining for a while remove the radiator cap start the car . Now press the accelerator from under the hood or have a friend sit in the car and press the gas pedal. Look down in the radiator and you should see water flowing easy. If you can not see the water flowing that easy it may be the radiator stooped up even thew you had the system flushed.
Make sure the electric fan is coming on and off as it should.
Now water pump could have some issues. I it is one of those water pumps that has a plastic impeller it could have some of the plastic impeller broke and not moving the water as it should.
Business Accounts
Answer for Membership
by: lherrouPosted on 2009-05-13 at 13:04:51ID: 24379061
brainbolt,
The hardest thing to diagnose is intermittent problems like you describe. At 170k miles, I'd be wondering how much you want to invest in this particular car to try to hunt the problem down. However, if you are going to stick with it, recognize that modern cars have complex electrical and emissions control systems, and if I had to take a guess, I would suspect the problem lies in one or both of those.
If it was a headgasket problem, I suspect you'd be seeing a different set of symptoms. Does your coolant have antifreeze in it? If so, can you pick up a smell of antifreeze near the tailpipe or does the car ever have white smoke emissions from the tailpipe? Are there any signs of bubbles (or oil) in the coolant when you remove the cap on the radiator itself? Do the plugs show signs of coolant damage? There's also a leakdown test that can be performed to test for this.
Overheating can also be caused by abnormal ignition, such as pre-ignition and detonation, which might be a better fit with the "running rough" problem you report.
Cheers,
LHerrou