Cooling issue...

[dimeadozen]

I have done Everything in my power to solve why my 87 overheats. 

I changed the thermostat,
I bought new hoses
I bought new rad and thermostat caps
I changed the fluid
I had to replace the radiator.
I had the car Professionally filled and checked at a shop.
I had the shop check the engine temp. They said my gauge was reading wrong... when it was going into the red... So i believed them
I replaced one valve cover that was leaking oil.

My Fiero is still overheating, and whats worse is since I got my car back, my temp gauge doesn't move when the engine heats up.
Also my car is only blowing cold air thru the vents. 

I had to drive it to another location and in the 10 minutes it opened up the check engine light.  And when I got there there was visible excess heat coming off the deck lid vents... U know the death steam...   

Its not steaming alot and It doesn't look to be burning coolant but I honestly don't know.


I'm praying its not a busted head gasket, but what else could it be???

I'm so close to being done this car and this problem is still a problem, and I am out of ideas.

[dguy]

First, calm down. 

Now...  there is no ECM error code for overheating.  If your Check Engine light is on, it will be due to something else which may or may not be related to the overheat condition.  Have you checked to see what error codes are being reported?


visible excess heat coming off the deck lid vents

Unless you're seeing steam or smoke from the decklid vents, don't sweat it.  Even a well-running Iron Duke will have visible heat waves issuing from the decklid vents once you stop & shut it down.


Professionally filled and checked at a shop

Not all shops these days are familiar with how to fill & burp a Fiero's cooling system.  There's more to it than filling the average front engine car...  Ideally they should have used a procedure similar to the "Coolant Fill" article at this link.


Now... forgive me for asking the obvious question, but are the radiator hoses, the radiator itself, and/or the heater core hoses hot to the touch when the engine is up to temp?

If your answers are "no", especially where it concerns the radiator & rad hoses, the short & sweet is that you have insufficient coolant flow.  Air lock or other blockage, bad water pump, etc.  I would start by making sure that there is no air in the system...

[2ML67]

No heat from heater core means there is either no fluid getting to it or the thermostat is stuck closed.
Remove the rear rad cap at the thermostat and remove the thermostat, now fill the engine with coolant till it will not take any more. Wait a bit to see if it goes down then fill it some more till the engine will not take any more fluid.
Put the cap back on and fire her up and let her run till the engine comes up to temp. I trust the heater pumping heat more then the temp gauge so put the heater control to defrost and turn the fan up so you will be able to feel the hot air when it comes out.
If the engine over heats with out hot air coming from the defrost then you have a blockage or a bad water pump or major air lock in the system. If hot air does come out then shut the engine off and let it cool for a while so you can remove the rear rad cap to top off the coolant and instal the thermostat. Dan 

[falcon_ca]

Remember that a Fiero never blow hot air out of the dash vent. Only from the defrost or floor.

[aaron88]

It sounds to me like you have air in your system causing the pump not to prime properly.  The problem with that scenario is that you likely also now have other damage, like cooked seals and gaskets.

Never trust a mechanic that doesn't also come over to you house for a beer from time to time.  And that you can verify that he (or she) does shit that you know no one else can do.  Other then that, role the dice.

Aaron

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[dimeadozen]

Ya, Thanks for the tips,

My decklid definitely is producing the death steam from the vents.

I had a second mechanic look at the issue and he found that there was a lack of coolant so he filled it up.

It ran fine for a bit. I got it home (about ten minutes stop go traffic lights)

It was blowing hot air thru the inside vents when I was venting the heat. Someone mentioned it should not do that? Only thru the floor?

Then it happened again, I was test driving the car on sunday and the engine light came on and this time the coolant was pouring out of the overfill tank.

Maybe he didn't properly fill the car, as I know this car needs a special procedure. I forgot to ask him if he did. I'll check Monday.

I really hope the seals are not cooked. I know the engine was hard pressed before I got it even tho it runs like new.

I had to change the lines and rad cus everything had ruptures in it. The hoses are warm to the touch when it runs.

What is wierd that I noticed is that the fan kicks on as soon as I power up the car, even when cold. IT is always running when the car is on no matter what.

My oil pressure drops also once the car heats up... the light comes on and I'm wondering if that is related...

And my temp gauge is useless as it looks like it is disengaged...

I'm gonna try 2ml67's tip and I will let you know how things go...

If what I just added changes things, I'm open to any more suggestions... Just don't ask me to throw it away I love my junker... its like my millenium falcon... She may not look like much but she's got it where it counts... just no light speed.

[dguy]

Don't worry about the radiator fan always running when the key is on.  If you're curious by all means investigate it later, but yours wouldn't be the first car where the rad fan has been hot-wired to deal with a bad fan switch or overheating issue.

Did you ever check the ECM error codes?

[dimeadozen]

I am not sure how to check ECM error codes and I don't have the OBD scantool...

I did notice something new...

I followed your fill tips and ran the car.

The rad fluid started to leak out the fill tank lid. I left the car to run figuring it would run some out as a cycle or something.

Then the car started to blow cold air in the cabin instead of the usual hot air so I turned it off

As soon as I turned it off, I heard the loudest clacking sound from under my car.

I looked under my car and saw my drivers side heater pipe knocking and there was a high pressure spray pissing out every time it would knock...

I think I may have found the air leak into the system, I just had to run the car really hot to find out where it was coming from.

I got the new pipes today and will replace them and refill the system to see if that solves the air leaking in issue. I'm praying it does.

Does this sound plausible?

As for the fan, It never ran like that until I took it into my mechanic and I am wondering if one of the mechanics fiddled with the car cus my temp gauge does not work at all ne more and my fan never kicks off. They never told me they did ne thing, so I don't wanna point fingers... its just odd, ya know?

Then again, finding a mechanic who I trust to work on my fiero is about as difficult as finding a fiero that I can trust to not give me problems lol.

[dimeadozen]

Hey If I take out the cooling pipes and replace them with long lengths of neoprene hose, will that cause any issues?

[aaron88]

To be honest, you are far beter off using plumbing hard copper.  Just be sure to paint it black so you don't look cheep.

That's the way I'm re-doing my car.  All hard copper except for flex joints and final connections.

Aaron

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[dimeadozen]

Well u see I bought the pair of pipes from the Fiero store, and I HAve them, but I dunno if I am gonna use them, cus they look really hard to put in, especially the part where u gotta fiddle with it in and around the suspension. I tried already and I think my car is not high enough off the ground to angle the pipe. Thats why I'm thinking of running straight pipe to the front then just before the wheel, I was thinking of running flex hose. The Copper is a good idea. Why is it cheap tho? Cus it goes green? Or does it rot out?

[FieroBUZZ]

The pipes are easier if it is up on a hoist, due to the contortions needed. 

If you just have a leak at one spot, cut the hard pipe on either side of the leak and bridge it with a hose and clamps.  It will work fine.

[dguy]

The Copper is a good idea. Why is it cheap tho? Cus it goes green? Or does it rot out?

It's not so much that copper is cheap, rather it may give some the impression that you cheaped-out by cobbling something up with plumbing parts from a hardware store rather than using the "real" thing.

[aaron88]

Don kind of hit it.  It's the perception not the actuality of it.  If you use copper you should paint it for "green" reasons.  Also the black paint will help the pipe to shed some extra heat.

Aaron

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[dimeadozen]

Ah ok I see. I already removed the whole pipe... I'm gonna see how high up I can jack the car then I will try and work the pipe. My other options r to take the car in and get it done or to do the copper piping and send back the pipes, cus I don't wanna break them and they cost me like 500 dollars lol The firo store is so overpriced.