Hi,

I'm hoping to pick up a 1992 Accord EX Coupé, however, the seller has stated there is problem with the temperature gauge, it fluctuates between high and low, independent of driving conditions.

I'm obviously wary of this, but i like the sound of the car otherwise. He stated that a mechanic connected a unit and showed the temperature was steady.


He has replaced the thermostat and flushed the radiator, checked the single sender wire and behind the gauges themselves. All appear connected, but hasn't done anything else other than a visual check on them.

Lastly, he states no boiling water etc and seems to run fine on long drives. He's only had the car 3 weeks, but states good reasons for now selling the car.


Can anyone offer any advice on how serious this could be? it sounds almost like a air lock.


Thanks.

 

Some parts stores have a radiator pressure tester that you put a deposit on it and get your money back when you return. The radiator should hold 15 psi. Also check that the cap can hold pressure.

As for the temperature gauge in the car, unplug the single wire of the sending unit. This will be on the passenger side of the cylinder head nearest the front bumper and have only one wire going to it. If the temperature gauge does not move, then the sending unit is likely faulty. Search the forum for temperature sending unit and you should find similar threads.

When buying a used car, it may be worth the money to get a buyers inspection from a mechanic. Especially since the car is nearing 20 years old.

 

Thanks for that, specifically on the sending wire, under what conditions will what happen to the gauge?

In this case the gauge operates normally except for the fluctuations whilst the car is running.

Thanks for your help

 

I just recently bought a 91 Accord SE with a similar problem. It fluctuates between 1/4 and 3/4.

The Seller told me that It may be the water pump, but my mechanic seems to think it is the fan switch He says it goes bad a lot on these cars.

I plan to change the temperature sending unit myself soon just to be sure but the car is not overheating and I have driven it almost 1K miles this week so that I can get a feel for any problems the car might have.

 

Under normal conditions. When the sending unit is unplugged and the wire is not touching anything, the gauge will stay at cold. If you touch that wire to ground, the gauge should rise to hot. When you ground that wire, turn off the key when the needle gets towards hot, so you don't damage the gauge/needle.

 

Thanks, the sender has been replaced apparently, so it's sounding like a gauge issue (hopefully) This being the case, i'm assuming the gauge will not rise correctly when tested?

 

If the gauge does something different, then it is either the wire, the cluster, or the temperature gauge.

 

Apparently the gauge goes up when the fans come on or the electric windows are used, any electric use causes it to climb.

 

So with it disconnected, the gauge moves a minute amount, i've not managed to get the seller to earth it yet.

Should i expect *any* movement, no matter how small, when it's disconnected?

 

I never did this test on my car. My guess is that the gauge might move slightly when the key is first turned to the II position. You want to ground that wire, and watch the gauge rise. If the gauge and wire act normally when unplugged and grounded, then the sending unit is the likely culprit.