1986 2.3 overheat ?

[marc1986]

My temp gauge goes to max hot in about 30 secs when starting in the morning after sitting all night. also getting heat from the heater in about the same time. New coolant temp sensor, radiator ,water pump, and thermostat. new coolant. After running about six miles, temp gauge says I,m cooking but no boiling sounds are heard from engine or radiator. Engine still running fairly smooth. the engine oil has a funky red ish brown look to it. oil is about 4000 miles old. when running the temp gauge never moves off hot.

Any ideas...thanks

 

[RonD]

The coolant temp SENDER is what Temp Gauge uses, sensor is for the computer

It is at the back of engine on Drivers side, drawing here: http://repairguide.autozone.com/zne...6b43f/80/21/b7/e1//small/0996b43f8021b7e1.jpg

To test if sender wire is working unplug it from sender and turn key on, temp gauge should be at cold, now ground that wire, temp gauge should go to HOT, if this happens the wiring and gauge are OK, replace sender.

Cold engine
Remove radiator cap
Start engine
Coolant should not come out of rad cap opening, if it does then you may have a blown head gasket
Put cap back on, engine still idling
feel upper rad hose, should be cold of course
Wait 2 minutes then feel it again, should STILL be cold, if not then new thermostat is not closed all the way.

Radiator on all vehicles is for EXTRA heat, 2.3l Lima engines don't generate much EXTRA heat, so radiator often never gets that warm, thermostat is there to keep engine coolant above 195degF, best for MPG and engine life

Wipe some oil from dipstick on white paper towel, to see true color.
Could someone have added ATF to the oil, this is often done to clean oil passages, doesn't hurt anything

 

[tomw]

If the other gauge(fuel) also works hinky, check the voltage regulator on the backside of the cluster. It 'chops' the 12-15V of the alternator down to a steady 7-ish(I think) so the voltage is stable no matter what the battery-alternator are doing. If failed, it could be sending too high voltage to the gauge(s).
I have never heard of a cold engine producing heat from the heater withing 30 seconds. A gauge that reads full hot within 30 seconds would be something the maker would want, as they could lean out the cold mix to beat emissions and economy standards if the engine could reach operating temperature that quickly. Startup is the worst time for emissions control, from what I have read. They'd beat a path to your door...
Is the upper radiator hose hot within 30 seconds? If so, the stat is borked. I do not think a 2.3 can produce heat that quickly.
tom

 

[marc1986]

Thanks for the information. I replaced the thermostat and temp sender.
the gauge was going up and down from cold to hot after about five minutes.
I followed the proceedures I've read on this forum for bleeding the air out of the coolant system. After several go arounds , the air seems to be out and everything seems to be back to normal...thank you.