ok so about 2 weeks ago my moms 94 accord ex give a lil problem i start the car in the morning the water temp shoots way above the "H". Now i can up with a couple ideas, fuse, sensor, and the gauge its self i wanted to know if any body here has ran into this problem before. thanks.

 

bump

 

Could you elaborate on the problem? Does the gauge stay there or does it go down after a while? I dont think that its a fuse, cuz the gauge wouldnt work at all if the fuse was burned out.

 

when you start the car, does it IMMEDIATELY go to hot or does it take some time?

if it IMMEDIATELY goes to HOT then I would guess a bad temp sensor

If it takes some time (like it slowly goes up to H) then I would guess a bad t-stat

If the t-stating cooling system are otherwise functional (IE fans are working, system is pressurized, no leaks, etc) then I would say blown head gasket.

 

sorry... its diff every time but the majoraity of the time the gauge just goes up at start. all the fans are working i checked all the hoses no lose of fluid.

 

you mean as soon as the engine starts running right?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by YeuEmMaiMai &raquo;</TD></TR><TR><TD CLASS="quote">you mean as soon as the engine starts running right?</TD></TR></TABLE>

ya in the morning of afternoon doesnt matter wat time when i start the car the gauge is pointed at "h" well unless the car is off but as soon as i start the car for the first min or less it will be at "c" then it will just to "H"

 

Its the coolant temperature sensor

 

First of all is the car actually overheating? If the water pump impeller has come off then it will overheat very quickly.
If the sensor is bad then you need to remove it, put it in the freezer for 20 mins, take it out and read the resistance across it immediately, then put it in some hot water for the same amount of time and then read the resistance again. Post your findings here

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by standbackimapro &raquo;</TD></TR><TR><TD CLASS="quote">Its the coolant temperature sensor </TD></TR></TABLE>where is this located?
thanks.

 

there are 4 on those two on the block under the distributor, and one and one on either t-stat houseing. the one that goes to the cluster is the front most senser on the block, also the smallest if I rember correctly.

 

Hey Hitech,

sorry to hijack your thread, but I have the exact same thing going on in my 1994 Accord LX.... as soon as the car starts up the gauge is on C, but after about a minute it goes to H, even if its been sitting in freezing cold all night.

The temp sending unit is what controls the temp gauge, and is a single wire connector and is located under the distributor, all the other connectors are 2 wire guys, there should be 2 for the electric fans, and 1 for the ECM. I'd first try replacing the temp sending unit, you can get one on Ebay or at your Honda dealer.

I replaced my temp sending unit, and it still does the same thing however. has anyone had this problem and successfully fixed it? I'm gonna try to get another gauge cluster in case its the gauge itself thats bad.

Any ideas?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by YeuEmMaiMai &raquo;</TD></TR><TR><TD CLASS="quote"> I would say blown head gasket.</TD></TR></TABLE>



Whats wrong with a correct and accurate diagnose?

The temp sensor can be tested for resistance 140 ohms cold engine and 30-40 ohms at full operating temp.

The gauge can be tested by grounding the sensor lead, then getting in the car and turn on the key, the gauge should move to the Hot, but don't let it peg out or leave the key on for a long time.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beaterhonda &raquo;</TD></TR><TR><TD CLASS="quote">Hey Hitech,

sorry to hijack your thread, but I have the exact same thing going on in my 1994 Accord LX.... as soon as the car starts up the gauge is on C, but after about a minute it goes to H, even if its been sitting in freezing cold all night.

The temp sending unit is what controls the temp gauge, and is a single wire connector and is located under the distributor, all the other connectors are 2 wire guys, there should be 2 for the electric fans, and 1 for the ECM. I'd first try replacing the temp sending unit, you can get one on Ebay or at your Honda dealer.

I replaced my temp sending unit, and it still does the same thing however. has anyone had this problem and successfully fixed it? I'm gonna try to get another gauge cluster in case its the gauge itself thats bad.

Any ideas?</TD></TR></TABLE>

I had the exact same symptoms (94 EX) and replaced the sending unit as well. it was a waste of 40 bux.

Already replaced the thermostat with a tested new OEM one. checked my installation twice.

Fan motors work. Checked my fuses, and they are fine too. Relays are ok.

I think it is the wiring between the guage and the sending unit. Maybe cracked insulation or something, because after idling it for 20 minutes, the needle drops back to right below half way again..... I am guessing that as the engine bay heats up, the moisture in the wires dries out, and the guage reads correctly.

Bad headgasket would not make the needle behave this way.

Any other ideas?

 

stupid electrical problems!!!! i also wasted the $35.... the more i think about it, it might be the gauge itself? The gauge is supposed to read all the way hot if you ground it the connector thats supposed to go to the sending unit...

if there really was a short to ground, it would read H even with the connector unplugged... mine only reads H when the connector is plugged.

I want to take my gauge cluster out and check the gauge itself to see if thats bad... anyone done this before? how can i trick the gauge into seeing if it reads correctly? I imagine applying voltage to it through different resistors should tell me if its doing its job but i want to see if anyone else has done this before.

Thanks!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beaterhonda &raquo;</TD></TR><TR><TD CLASS="quote"> The gauge is supposed to read all the way hot if you ground it the connector thats supposed to go to the sending unit...
</TD></TR></TABLE>

I didn't know this. Maybe I will try unplugging the harness from the sensor to see if anything changes when it starts reading hottttt.

If not, then something wrong in the harness or guage. (assuming this is true)

 

Hey Fellas,

I fixed my temp gauge problem this weekend... turned out it was the gauge itself in the dashboard. If you have the same symptoms (gauge goes to H as soon as you put the key in) its worth checking out the gauge itself.

I got a used gauge out of a used complete gauge cluster i bought on ebay... if you turn the gauge over (backside) you'll see there are screws holding each gauge to the circuit board. after you remove the correct screws, then press the tabs in that will allow you to take the bezel off the front... once you take the bezel out the gauge will come out the front.

You only need to swap gauges if you want the same odometer reading as you had before... in my case the cluster i bought had more miles than my car. it turned out the two temp gauges were different sizes on the back side (had different p/n's too) so i swapped the speedo/odometer gauge from my car into the new cluster instead.

obviously you need to take your gauge cluster out to do this but not too bad, with a haynes manual it took me about 1 hour to get the cluster out, another 30 mins to test the new one, and then 1 more to button everything up.

put it all together it works like a charm!!!

I can give more details if anyone has a question, just shoot me an email!