1986 firebird hard start
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1986 firebird hard start
hi
we just purchased a 86 firebird transam with fuel injection. When i try to start it , it can be hard to start. Once it starts and runs a little it will start easy over and over, but if you turn if off and let it sit 15 minutes its hard to start again.
Recently my son parked it up hill over night and oddly it started right away.
Fuel filter is changed, distributor rotor and distributor cap replaced
any help would be appreciated
we just purchased a 86 firebird transam with fuel injection. When i try to start it , it can be hard to start. Once it starts and runs a little it will start easy over and over, but if you turn if off and let it sit 15 minutes its hard to start again.
Recently my son parked it up hill over night and oddly it started right away.
Fuel filter is changed, distributor rotor and distributor cap replaced
any help would be appreciated
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Re: 1986 firebird hard start
Welcome Aboard!
Beginning with the basics, when the engine is cranked (starter operated) does it turn at a reasonably normal speed or seem difficult to turn or struggling? If it struggles, the cranking voltage may be low and that could affect both the electric fuel pump running pressure and the ignition system.
Once it is running and at a relatively normal coolant temperature does it run acceptably well or continue to have running problems? If it runs reasonably well and has no other issues, the "usual suspects" including the ignition system, timing, inlet air flow, and mechanical problems can possibly be ignored for now.
The next critical item is fuel delivery, and specifically the fuel pressure when cranking and immediately after shutdown.
Beginning with the basics, when the engine is cranked (starter operated) does it turn at a reasonably normal speed or seem difficult to turn or struggling? If it struggles, the cranking voltage may be low and that could affect both the electric fuel pump running pressure and the ignition system.
Once it is running and at a relatively normal coolant temperature does it run acceptably well or continue to have running problems? If it runs reasonably well and has no other issues, the "usual suspects" including the ignition system, timing, inlet air flow, and mechanical problems can possibly be ignored for now.
The next critical item is fuel delivery, and specifically the fuel pressure when cranking and immediately after shutdown.
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Joined: Jan 2000
Posts: 19,659
Likes: 310
Re: 1986 firebird hard start
Correct - The test port is on the right side fuel rail. Expect about 45 PSI with the pump running and engine off, and about 37 PSI with the engine running if everything is working normally. Once the engine is shut off, fuel pressure should hold at the last running pressure if the fuel pump check valve is intact, the fuel pressure regulator is not leaking through, and injectors are not leaking internally.
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Junior Member
Joined: Feb 2023
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Re: 1986 firebird hard start
i finally replaced the fuel pressure regulator but also found the compression 60 to 65 psi at the cylinders. We tore it apart and refreshed/ rebuilt the engine
it took forever and was a major project
thanks again
oh i lost the bolt and nut for the starter bracket
does anyone know the bolt and nut size if cant seem to find the size
it took forever and was a major project
thanks again
oh i lost the bolt and nut for the starter bracket
does anyone know the bolt and nut size if cant seem to find the size
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