another temp gauge problem

[AZmike]

My temperature gauge works perfectly about 75% of the time. Otherwise it says my car is overheating. Has any one else had similar problems? Should I try replacing the gauge or the temperature sender first? I'm hoping it's the sender since that's so easy to switch out, but I wanted to see if anyone already knows so I won't be guessing what what part is at fault.

Thanks

[anchovies]

maybe u r overheating?
to test the temp sending gauge, ground the single wire to any part of the car and the gauge should be at max (if i remembered correctly, don't quote me on this)

hope it helps

[rocky2]

Get a hold of a tempurture gauge setup...the one with the bulb attached to the end of the complete setup and duct tape the bulb to the top radiator hose but don't wrap tight and run wire up through hood where it doesn't get smashed just to see what it it doing for real.;)

[njpeter]

Since overheating is the death bell for any accord, you want to measure the radiator temp. Might be simpler to just stick a new thermo in..never a bad idea, esp in summer.

cheapo first step, bleed air from bleeder near distributor

Getting a thermometer into the radiator would give you an idea, but a sticky thermo can devestate you. Also check fan switch operation( with thermo in radiator ). I've been told that 3g radiators are crap, but I've not had an issue..dealer nicked me once for one..straight rip off..the tech must have overpressurized it and blew the core..wasn't leaking at all..turned out it was the first sign of impending head gasket failure..bet they put some stopleak in it.

that was my last trip to a certain long isalnd honda dealership shop.

time is money however..and that was the rule of that day..now when I have to take a sick day to fix my car, I say "hmmm..my shop rate is $80 an hour..that's a big fat raise!"

sage advice-
don't trust the gage.
running the heater full on can save your engine if you are overheating
"i didn't see the speed limit sign officer"-doesn't work
wash hands after handling used motor oil or fuel
new does not mean reliable, just expensive
the best things in life were made between 1986 and 1989 :-)

[HostileJava]

You might as well replace the thermostat and gasket and see if that solves your problem, it should only cost you $5 dollars total if you do it yourself.

[AZmike]

Thanks for the suggestions, but I think you guys misunderstood. Occasionally the gauge will shoot up, then fall back down to the warmed-up normal operating position. Sometimes it will stay up for a minute or two, other times for only a few seconds. When the needle is off, it usually goes above the markings on the gauge. Sometimes it goes maybe 80% of the way up. All of the gauge movements are fast. If it moved up slowly i would wonder about my cooling system. Since it moves up so quickly and i know that the car has had this problem for 20k+ miles I'm pretty sure that the cooling system itself is still running properly. I have bled the system and there is no air. I guess this is more of an electrical question. Is the temperature sender or the gauge itself that is likely to be responsible for these bad readings? I'd like to be able to trust my gauges so having one reading completely wrong from time to time is sometiming i'd like to fix.

By the way, my speedometer reads exactly 10% high (70 mph on gauge is really more like 63 mph, a reading of 45 mph is acually closer to 41 mph). If you know someone with a GPS you can test yours too. If other cars had the same problem it could explain why some people can get higher speeds in a certain gear, higher top speeds, etc. than you'd expect.

[DanG86LX]

Look up the thread at what ANCHOVIES just posted! Your sender wire may short to ground from time to time..

[anchovies]

when the gauge shoots up, does your fan come on? if it does that likely means your cooling system has some trouble instead of your gauge or sensor....it takes a minute or two for the gauge to come back down when the fan turns on
or just grab a new sender sensor...see if that fixes it

[AZmike]

the fan seems to operate independently of the gauge. it will shoot back down just like it 'found' its lost signal. I think that those senders are pretty cheap so i'll give that a try. thanks everyone.

[anchovies]

about $20, less than that i think..i forgot
and it's at an angle to the thermostate housing
messed that up and it's a $200 job
i've been there

[AZmike]

I just figured I'd post what ended up being the solution. I replaced my thermostat and some hoses and cleaned the temp sender and it's cable. That didn't really help my gauage problem. On the plus side I found that my old thermostat had enough gunk clogging it open that I knew why my car would overcool going 65 mi/hr in 35 degree F air.

The temp sender looked good and tested good, but I went ahead and screwed in another sender from a u-pull-it yard: problem solved.

Thanks for all the recommendations guys. It's nice to have this fixed after having this problem ever since I got the car. Now to fix that slow-speed wobble in the speedo....archive review time