I have a 96 Chevy S10. The heater started working intermittently and the temp gauge rises and falls...?

Question

The other guages seem to be acting funny also. The oil pressure is higher than normal and I don't think the gas guage is working correctly either. The temp guage rises and gets close to the red zone but falls if I let off the fuel. Friends at work have suggested the thermostat, heater coil, fuses, and water pump. I checked all fluids this morning. I added some coolant (it was a little low) The fuse for the gauges is fine, but I replaced it anyway. The top hose on the radiator was getting warm, so I assume the thermostat is working. There were no leaks from the water pump, but I guess it could be going out. Can anyone help narrow down this problem before I have to put the truck in the shop? Thanks for any help you can give me.

Answer 1

I think you have an electrical problem with your vehicle. I would start by checking battery connections,alternator output then check for draws. With all of the electrical things going wrong at the same time it could be alternator,battery,wiring etc.

Answer 2

If cold weather then oil pressure being up is normal. Electric guages act awkward when cold. Coolant temp swings (within limits) are normal. Wild temp swings with overflow problems indicate air pocket formation in the coolant system and can be simply resolved by drilling small1/8 in. holes into the outer ring of the thermostat-2 holes and no more.This allows coolant to circulate reguardless of temp-thus eliminating air pockets. Cardboard in front of the Radiator will help to maintain heat in the engine.Be careful to adjust to changing conditions.

Answer 3

This ramp up and down of engine temp can sometimes be traced to a problem with Dex-Cool antifreeze (often orange colored). The mixture can coagulate and clog up your system if there is an air space in your radiator/coolant system.

This condition should be easy to diagnose. The sign will be that your radiator cap and its spring will be coated with a heavy sludge, you may also see this material in the radiator itself.

If this is the case, you have to do one or two heavy duty chemical flushes to try and rid your system of these clogs. If you can't do it with over-the-counter products, GM has products specialized for this treatment, but it must be procured through their dealers.

When refilling your system, don't forget to add a lubricant additive for your water pump, it'll likely need that after that acid flush.

Dex-Cool is a good product providing you keep an eye on your radiator, don't just rely on your overflow bottle having the right level.

Answer 4

When your temp guage is eratic, the very first thing you need to do is replace the thermostat. here, $7. http://www.drivewire.com/chevyparts/catalog/chevys10thermostat.html
This is almost like a cureall for everything. Rpms jump, replace thermostat, problem solved... guages going nuts, replace thermostat, problem solved.
Do that first, that will solve 90% of your problems.

Answer 5

Replace the gauge, right down to where the sending unit is in the coolant. Methinks you have a lemon unit, and thats the simple answer instead of fooling around with "snapping" needles back on. once the needle is off, the accuracy of the thing is toast, regardless of if it operates smoothly after "snapping" it back on

Answer 6

To save yourself a lot of waisted time go to a well equipped Chevrolet dealer and allow them to insert a diagnostic cable connector to your on board computer in your S-10. You sound like my kind of guy as I like to find causes to everything on my S-10. There are all kinds of headache solenoids hidden everywhere and I'm positive you have an electrical switch and or a malfunctioning temperature solenoid causing all of these on dash problems.

Answer 7

I would check the ground straps and Neg side of batt

That is elec. problem and probably ground straps.

Answer 8

psst..check your batter cable connections.

Answer 9

I believe you have the anwser!