Temp gauge failure/burning plastic smell from under front hood? (Page 2/3)
Patrick JUN 22, 02:10 AM

quote
Originally posted by theogre:

3-In-One and many others are the wrong oil for this use and can bind up far worse.
Is very hard to clean out old oil and crap and "new" oil can react badly with them over hours to weeks.

Ac/heat blowers for cars aren't only ones w/ same problem. Many 120/240 AC fans of all kinds have same issues and using wrong lube to "fix" them don't last long either.



I knew you were going to say this. I promise, perhaps by the end of the year, to report back on the status of my blower motor!

viperine JUN 22, 03:17 AM
The pegged gauge is the needle getting stuck in the foam that prevents dash backlighting from bleeding through the cluster from the wrong angles. The quick fix is a good pothole to jar it loose. The correct fix is swapping two very specific wires that feed into the cluster, as well as two wires at the sending unit/switch, which is located at the corner of the engine cylinder head quite near the distributor. Search for "temp gauge fix" to find out the exact procedure.

It may have worked itself loose for now, but it will happen again. You will notice the needle making a lot of movement each time you start the car. It is not supposed to move like that, and was a factory mistake.

As for the burning smell, pull the blower motor (what, 6 bolts?) And the rubber tube attached to it. You should be able to get at least some idea of imminent danger, though further peeking will be peace of mind. All fieros should be inspected here now and again, it's just so common.

I suspect you overheated and smelled hot coolant on various underhood plastics. The cooling system needs gone through, starting with the aforementioned thermostat cap removal to ensure proper coolant level.

All of this is very well documented on this forum. Do try your air conditioning buttons, these turn your cooling fans on automatically, regardless of coolant temp. Quick way to rule out a bad cooling fan.

Our beloved cars can drive quite a while without the fan kicking on as long as you regularly exceed 30 mph. Stop and go traffic or idling a while is where we find out something isn't working as it should.

Bringing the thermostat to a boil to observe it opening visually is simple. Water boils at a higher temp than the thermostat is due to open at. Thermostat: 195 if stock. Water boils at 212. Boiling water but no thermostat movement? Need a new one.

The list goes on. This is just the basic stuff to start with.
chaotichamster9 JUN 22, 12:32 PM

quote
Originally posted by viperine:

The pegged gauge is the needle getting stuck in the foam that prevents dash backlighting from bleeding through the cluster from the wrong angles. The quick fix is a good pothole to jar it loose. The correct fix is swapping two very specific wires that feed into the cluster, as well as two wires at the sending unit/switch, which is located at the corner of the engine cylinder head quite near the distributor. Search for "temp gauge fix" to find out the exact procedure.

It may have worked itself loose for now, but it will happen again. You will notice the needle making a lot of movement each time you start the car. It is not supposed to move like that, and was a factory mistake.

As for the burning smell, pull the blower motor (what, 6 bolts?) And the rubber tube attached to it. You should be able to get at least some idea of imminent danger, though further peeking will be peace of mind. All fieros should be inspected here now and again, it's just so common.

I suspect you overheated and smelled hot coolant on various underhood plastics. The cooling system needs gone through, starting with the aforementioned thermostat cap removal to ensure proper coolant level.

All of this is very well documented on this forum. Do try your air conditioning buttons, these turn your cooling fans on automatically, regardless of coolant temp. Quick way to rule out a bad cooling fan.

Our beloved cars can drive quite a while without the fan kicking on as long as you regularly exceed 30 mph. Stop and go traffic or idling a while is where we find out something isn't working as it should.

Bringing the thermostat to a boil to observe it opening visually is simple. Water boils at a higher temp than the thermostat is due to open at. Thermostat: 195 if stock. Water boils at 212. Boiling water but no thermostat movement? Need a new one.

The list goes on. This is just the basic stuff to start with.



These are all great suggestions, I too believe the smell may have been coolant getting kicked up by the fan and hitting plastic under the hood (some of the wires near the A/C accumulator had coolant on them). To visually inspect the thermostat working I need to open the cap, start the car, and look for fluid movement with the cap off correct?

As for the needle, I will keep an eye on it, if it gets stuck again I will try that temp gauge fix, still trying to locate where the sending unit is, I think I’ve got it, just looks pretty buried under other wires. Large detail I should have mentioned: I actually drove the car 16 hours home, performed flawlessly the whole way, just noticed these issues after work yesterday.
Patrick JUN 22, 01:12 PM

quote
Originally posted by chaotichamster9:

To visually inspect the thermostat working I need to open the cap, start the car, and look for fluid movement with the cap off correct?



Ummm... not the way I'd do it. Someone else may wish to correct me, but I suspect you'd get coolant exiting the open thermostat housing in short order!

To test the thermostat, it might be less messy to put it in a pot of water on the stove and see if it opens as the water reaches the temperature rating of the thermostat. Factory rating is 195°F. It should be fully open at least by the time the water is boiling.

[This message has been edited by Patrick (edited 06-22-2019).]

viperine JUN 22, 02:19 PM
Like Patrick said, boil a pot of water. I run a string through the thermostat and tie it to a stick/utensil to keep the thermostat suspended in the water. Allowing the thermostat to rest in the bottom of the pan may give you a false reading (pan metal will heat faster than the water).

You can safely burp the cooling system with the thermostat cap removed if the engine is presently cold. You will be covered in coolant if the engine warms up before you replace the cap. So while the engine can be run without the cap, it is only while cold for a brief period. Do NOT open a radiator or thermostat cap on a hot car. You WILL get burned.
chaotichamster9 JUN 22, 09:43 PM
Took a flashlight under the front hood and saw these wires near the brake booster. Does that look normal? Maybe that is the cause of the burnt plastic smell?Wires
Gall757 JUN 22, 10:02 PM
normal.
tshark JUN 22, 10:04 PM
That gunk is water sealer.
tshark JUN 22, 10:05 PM

quote
Originally posted by chaotichamster9:


These are all great suggestions, I too believe the smell may have been coolant getting kicked up by the fan and hitting plastic under the hood (some of the wires near the A/C accumulator had coolant on them). To visually inspect the thermostat working I need to open the cap, start the car, and look for fluid movement with the cap off correct?

As for the needle, I will keep an eye on it, if it gets stuck again I will try that temp gauge fix, still trying to locate where the sending unit is, I think I’ve got it, just looks pretty buried under other wires. Large detail I should have mentioned: I actually drove the car 16 hours home, performed flawlessly the whole way, just noticed these issues after work yesterday.



The area by the AC accumulator should be sealed from the coolant. How the heck did it get in there?
fierosound JUN 23, 10:35 AM

quote
Originally posted by tshark:

The area by the AC accumulator should be sealed from the coolant. How the heck did it get in there?



It's probably oil leaking from the A/C lines. The A/C isn't working because the system is low.

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