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[Pegasus]

That's where I've been checking, its got no pressure

[jwrape]

Try hot wiring the fuel pump from the ECM plug in the console under the cigarertte lighter panel. If you can run the fuel pump from there you might have the same issue I had with mine where the primary fuel circuit is bad.

[Pegasus]

Would I need a new ECM to fix that?

[jwrape]

Well, I bought a new one to try to fix mine and it messed up again. Since your secondary fuel circuit runs through your oil pressure sensor, you definately want to replace that. That is what I had to do to get it to work at all. Bascially, I don't know what makes the primary circuit fail but the secondary circuit works good as long as the oil pressure sensor is good.
After it left me stranded a couple times, I just put a switch beside the cigarette lighter that hot wires the fuel pump if ever the oil pressure sensor goes out again  I won't be stranded again

[Fierofool]

I'm not positive, but it may be possible for either the FP relay or the Oil Pressure Sensor to cause a short in the ECM.  The primary FP circuit is through the relay.  The FP circuit in the Oil Pressure Sensor is only a secondary system, designed to keep the car running should the primary circuit fail.  It will activate the FP when it builds the required pressure during cranking.  On older engines, this can sometimes lead to long cranking times.  On faulty pressure sensors that show unusually high pressure or stay pegged when the engine isn't running may be sending voltage through the ECM at those times. 

[jwrape]

I'm not positive, but it may be possible for either the FP relay or the Oil Pressure Sensor to cause a short in the ECM.  The primary FP circuit is through the relay.  The FP circuit in the Oil Pressure Sensor is only a secondary system, designed to keep the car running should the primary circuit fail.  It will activate the FP when it builds the required pressure during cranking.  On older engines, this can sometimes lead to long cranking times.  On faulty pressure sensors that show unusually high pressure or stay pegged when the engine isn't running may be sending voltage through the ECM at those times.

^^^^Yep, what he said^^^^^

[85GT]

when my 85 GT was cutting out sometimes and the fuel pump would not run the problem i found after changing 2 fuel pumps was the plug on the firewall in the engine compartment.. i cut off both ends of plug spliced wires together and have not had a problem in over 8 months......

[Pegasus]

It's Alive! IT'S ALIVE!!!!

[Donster]

It's Alive! IT'S ALIVE!!!!

Awesome!

\D

[Pegasus]

I made it about a mile down the road before it overheated. I need to flush the cooling system. Do 85 GTs have power brakes? It sure didnt feel like it, but after i parked it I took off the cap and the fluid was yellow so I'll be flushing the brakelines

[Roger]

I believe they all had power brakes. It's (brake fluid) a faint yellow. Don't mix synthetic with DOT 3 (or 4).
You may want to check if you have vacuum at the resevoir first before bleeding the system.
Considering the age, it would be best to purge/bleed ALL of the old fluid with new.

As for flushing the cooling system due to over-heating, be sure you are familiar with purging the system of ALL air when re-filling. Also check both radiator caps for cracks in the seals and replace them (if bad).

A great place to have you cooling system cleaned is to contact SIMS RADIATOR in Lawrenceville. They do excellent work.

[Fierofool]

Yes, Sims Radiator has been around Atlanta for a long long time.  I'm surprised they have no more locations than they have.  The closest one to Carrolton is in Decatur.  For radiators, heater cores, or AC condensers and evaporators, it's a good source for purchase or repair. 

In case you don't know, you don't fill a Fiero at the Radiator.  If the system's empty, you can fill the radiator until it's full, then put the cap on.  Fill the recovery tank, then go to the engine bay and finish filling according to a special procedure, through the thermostat housing.  When it comes time to refill, come back to this thread and someone will guide you through it. 

[Pegasus]

I believe the 'burping' procedure is in the Haynes manual. The coolant in the radiator was light-medium brown.

[Fierofool]

Sounds like it sat for a while without antifreeze.  You'd probably be wise to remove the rad cap, stick a water hose into the thermostat housing and let the water run.  If it has been sitting without antifreeze, you may have damage to the water pump impeller and to the freeze plugs.  Keep an eye on the temp when you get it going. 

Burping is pretty simple.  Fill the radiator and recovery tank, remove the thermostat cap and thermostat and fill at the thermostat housing.  Leave the thermostat out, put the cap on and let it run for 3-5 minutes.  Remove the thermostat cap, top off, replace the thermostat and cap and you should be good to go. 

[Fierofool]

Pegasus, something just occurred to me.  Regarding power brakes.  Roger is correct that all Fieros were equipped with power brakes.  Your problem may be in that the car sat for a long time.  The 84-87 Fiero has phenolic pistons in the front calipers.  When the car sits for prolonged periods, those pistons tend to stick.  It may be that you're only stopping with your rear brakes.  You may need to replace the calipers or rebuild them using aluminum pistons.