Starting problems

[Observer]

81 Fiat Spider

Starts fine and runs well, then when I switch off it won't start again.
Engine is turning over but won't catch.
Today it did it again, I held the pedal to the floor and it started (with a sputter), but lots of smoke came out the exhaust.
Then she ran fine

[rlux4]

There are a few things to check. Make sure you have full, smooth operation of the flap in the air flow meter (AFM). If you still have the factory inline fuse for the fuel pump that goes to the dual relay it could be loosing contact which would shut off the pump. This is a common problem that causes intermittent no starts, or even sudden shut down. Check that the two injector grounds on the rear, outboard side of the intake plenum are making good contact to clean metal. How are the wires under the dizzy cap for the magnetic pick up?
Check each component, it's common for people to think "it can't be that" only to find it was after all else failed. I was guilty of that when I first got my car and Mark suggested I check my flap movement. It was OK as far as I tested it, but got sticky when it got past 1/2 way open. I had to do a lot of wasted troubleshooting before I went back to the flap. Mark won't let me forget it either!
Ron

[Observer]

Checked the fuse, all seems fine
wires good under the dis cap.
Flap in Air flow meter all cleaned and working well.

Car started ran sweet and then once shut off, again won't start. Annoying

[So Cal Mark]

if the problem is only on a hot restart, you may have a leaking injector that is causing a flooding situation, or a cold start injector that is being energized when it's not needed. Lots more information would be helpful

[chuckcloutier]

My 81 did that and it was the ignition switch, also a common problem in these older Fiats.

[rlux4]

Mark has a good point; if it blows out smoke then smooths out it sounds like it's flooded. A leaky injector would cause this. They can stick in the open position, or not quite close if they're gummed up. You could test if your cold start injector is the culprit by disconnecting the hose to it and plug it securely. A barbed fitting with a clamp would be good, it has a lot of pressure in the line when running.
Ron

[Observer]

I will check the injectors

As for the ignition, why would it work when the car has cooled down vs hot? Just asking

[rlux4]

A poor connection causes resistance in electrical systems. It's not the engine heat that would affect the ignition wiring, it's the heat from this resistance, which would dissipate when the current stops flowing.
Ron

[Observer]

A poor connection causes resistance in electrical systems. It's not the engine heat that would affect the ignition wiring, it's the heat from this resistance, which would dissipate when the current stops flowing.
Ron

Now you see why I need to come here Makes complete sense! Thanks

[Observer]

Checked the ignition switch connection and two wires are scorched, the brown and red.
Did some cleaning & will test it tomorrow

[Observer]

[quote="Observer"]Checked the ignition switch connection and two wires are scorched, the brown and red.
Did some cleaning & will test it tomorrow[/quote

Still no go! Back to square one

[Observer]

Today the car started ran and then would not start after sitting for 45min.
I could smell alot of fuel. Pulled the cold start injector and she started right up.
Not sure if it is the problem but it is a start.

Anyone have the same experience?

[jimmycakes401]

I'm having this exact issue right now. Was it the cold switch all along? The PO had started to rig some sort of shut off switch to the cold start. I wonder if that's what they were doing... I reconfigured everything to stock...

[dutchgeordie]

Today the car started ran and then would not start after sitting for 45min.
I could smell alot of fuel. Pulled the cold start injector and she started right up.
Not sure if it is the problem but it is a start.

Anyone have the same experience?

I've got exactly the same problem and quick fix to get going again by pulling the cold start injector.
Has anyone found out what's causing this and how to properly fix it?