Question about 1986 Pontiac Fiero

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86 fiero thermostat and exhaust problem

Hi i replaced my thermostat and now it wont stay in its place it keeps turning sideways in the housing i dont get it and then it also hesitates at take off and after only running for a few minutes the exhaust manifolds turn bright red. I thought maybe the cat was pluged but i replaced it and it still does it what would cause these problems need help fast!!!! thank you Nick

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The thermostat is held in place by a rubber seal around it and the access cap. One of those is allowing the thermostat to move freely.

The bright red manifolds indicate that combustion is occurring in the exhaust manifold. This is usually a retarded ignition timing issue. Check your timing and see if that helps the hesitation at idle.

Good luck,

Rebel Faggioli

Posted on Apr 05, 2013


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SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi there,
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Good luck!

Posted on Jan 02, 2017

  • 1861 Answers

SOURCE: How many air/fuel or oxygen sensors are on the 2002 Prerunner 4cylinder?

The air-fuel sensor is located BELOW the manifold, on the side of the head pipe. You would need to be under the vehicle to see it.
That sensor is commonly called "bank one/sensor one".

Posted on Sep 09, 2008

  • 159 Answers

SOURCE: 2004 caviler exhaust is glowing

Check the egr flow,if it's stuck in the open position it will cause a rough idle and over heated exhaust temptures.EGR= exhaust gas recirculation

Posted on Dec 25, 2008

  • 343 Answers

SOURCE: 1986 Pontiac Fiero V6 2.8L rebuilt..I started it

That is usually from a clogged catalytic convertor and/or the pre-cat or collector that sits in between the manifold and the cat. If you left the pre-cat on, remove it and see what the result is.

Posted on Jun 03, 2010

  • 47 Answers

SOURCE: how to change struts on 86 pontiac fiero

Jack up car.
Remove tires on back.
Remove Nut on top of each strut, located inside engine hatch.
Remove lower bolts from spindle.
Remove strut.
Use spring compressor to remove springs.
Reverse procedure to replace.

Posted on Sep 12, 2010

SOURCE: is it normal for v6

Yes, they are made of a very thin steel, so watch for cracks in them.

When the time comes, here is a good source for parts:

Hope this helps.

Posted on Feb 14, 2011

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1 Answer

How to fush heater core in my 86' Pontiac Fiero GT?

If you need to flush the core you would be better to change it. It would get flushed when you flush the entire system. Also try changing you thermostat that is the usual first cause of running hot or a bad water pump. Good Luck!

Jun 17, 2014 | 1986 Pontiac Fiero

1 Answer

What to disassemble to change thermostat

You will need to remove your air cleaner and duct assembly. You will then see the thermostat housing sandwiched between the back of the intake manifold and the exhaust crossover pipe. The service manual says to remove the exhaust crossover pipe, but trust me, you do not want to attempt this unless you have access to a torch to heat the nuts that hold the thing to the exhaust manifolds. If you break a stud, then you are going to be removing an exhaust manifold for broken stud removal. If you take the 8mm screws out of the heat shield on the exhaust crossover pipe, you can wiggle the heat shield out. This will provide enough room to get the lower thermostat housing bolt out. It is a pain to do it this way, but it works and will prevent broken exhaust pipe studs. Sometimes the little 8mm bolts will also break, but since they only hold the heat shield, it is of no great consequence.

Then all you have to do is remove the two bolts that hold the thermostat housing to the manifold. The thermostat is directly under it.
Then the only other real "trick" is getting the thermostat and O-ring to stay in the correct position while you put the thermostat bolts back in. A trick that I use is a small wooden wedge. I put the thermostat housing into place over the thermostat and O-ring, then place mt wedge between the thermostat housing and the crossover pipe to hold the thermostat housing in place while I start the bolts. Otherwise, the thermostat tends to slide out the bottom while you are trying to get the bolts started.

Let me know how it goes...

Jun 16, 2012 | 2002 Buick Rendezvous

2 Answers

My 86 Fiero GT only has 58,000 miles, it has been in a climate controlled storage building most of its life, so, it has sat, it had a new fuel pump and strainer basket, and filter installed and old gas...

I would drain and replace the gas, old gas will cause this sort of problem.

If you have already changed the gas, first you need to check the fuel pressure, there is a location the fuel rail to attach a gauge (looks like a a/c refill fitting)

If you have good gas pressure, you likely have 1 or more clogged injectors, you can try and clean them, or simply swap them out.

A good source for parts is fierostore .com

Hope this helps.

Jan 02, 2011 | 1986 Pontiac Fiero

1 Answer

8 fiero stops working , will not turn over , after a while turns on like nothings wrong, stops while being driven. sometimes in morning will not turn on and sometimes it does, when it does not turn on i...

look around the exhaust manifold there is a wire that has melted and it is shorting out hope this helps you tape it up and pull it away from the exhaust with a zip tie so it dont happen any more

May 04, 2010 | 1987 Pontiac Fiero

1 Answer

How to change struts on 86 pontiac fiero

Jack up car.
Remove tires on back.
Remove Nut on top of each strut, located inside engine hatch.
Remove lower bolts from spindle.
Remove strut.
Use spring compressor to remove springs.
Reverse procedure to replace.

Apr 30, 2010 | 1986 Pontiac Fiero

1 Answer

My 86 Fiero SE clutch master cylinder is weeping

Replace it. Not a difficult job. Be careful the bracket on the V6 4spd. isn't strong so don't break it while loosening the slave cylinder retaining nuts.

Good luck,

Rebel Faggioli

Dec 30, 2009 | 1986 Pontiac Fiero

1 Answer

88 fiero starts on it own, but wont stay running.

the brain is not sending the proper fuel pressure codes to the fuel rail to evenly distribute the fuel to the intake and fuel rail.
perform a fuel pressure test check on it ok? also run a diagnostic scan on it and see what codes come out.

Jul 25, 2009 | 1988 Pontiac Fiero

3 Answers

Overheating Fiero

well fieros are very different cars you need to fill collent in a speical way so air doesnt get in the lines most fiero owners do not know this but it very important The best way to tell it is for wikipedia
Cooling system issues
With an already hot normal operating temperature of 220 °F (104 °C) prior to the recall switching to a 195 °F (91 °C) thermostat, the mid-mounted engine utilized long pipes to carry coolant to the front-mounted radiator. This demanded that a special coolant filling procedure be followed to prevent severe overheating. Simply pouring coolant into the thermostat housing (on the engine) would leave an air bubble in the radiator, while adding coolant just to the radiator would leave an air bubble in the engine's coolant passages. Proper procedure (with engine idling and the thermostat removed, filling the thermostat housing, burping the bubble out of the radiator by cracking open the radiator cap until coolant exits) must be followed in order to ensure an air-free cooling system.
A second problem has become common as more Fieros are being serviced by shops unfamiliar with their design. The under-body coolant tubes are positioned in such a way that a casual glance beneath the car will not suggest their fragility. As a result, many have been crushed by shop lifts, resulting in a near complete lack of engine cooling. The age of the car means that even GM dealerships may now be unaware of the proper jacking methods.
Lastly, the absence of a spare tire (at the front of the car, right behind the radiator) could have an effect on coolant system performance. i dont know who wrote this and i dont take credit for it

Feb 25, 2009 | 1986 Pontiac Fiero

2 Answers

Where is my thermostat located on a 1995 buick century

follow top radatior hose or lower it should be a housen with two bolts

Jul 26, 2008 | 2001 Buick Century

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