ALFAGTV6.COM

I posted this same topic on the BB...

A little over a year ago my '85 GTV6 began to die suddenly, as if it had run out of fuel, so I stuck it in the shed with plans to work in it when the weather cooled down a bit. Well, we had a series of setbacks (house fire, some medical issues, etc.) so that I am just now getting back to it.

Got it to run briefly yesterday-it purred for around 10 min. then just died. Car has a FI duty-cycle meter, and just before it quit the duty cycle went to like 90% suddenly (at idle) and died. Pugs are sooty black, so I think it is going full rich for some reason.

I've tried searching for a similar problem, but my computer is going tits up so that endeavor is not going too well either!

Any suggestions?
Thanks!
Jeff Lang

Could the high duty cycle be ECU response to fuel starvation? Could fuel line restriction cause this? I couldn't work on car today, so I'm trying to hatch a coherent plan for tomorrow.
Thanks,
Jeff Lang

Jeff the stock L-Jet system doesn't run "closed loop" at idle,in other words the ECU doesn't read the O2 sensor output so the computer can't change the injector duty cycle.The ECU runs an internal MAP at idle for fueling.Have you been through your cold-start circuit components to ensure they are all within spec.? You should also check your throttle switch to make sure the contact is closing when the throttle plate is closed.

Thanks Murray-
I understand the open loop at idle...I should have clarified things. I meant that this problem has also happened at highway speeds with a warm engine (closed loop). Right now the cold start injector is disconnected. Will check throttle switch in AM. What about fuel line restriction? I've not smelled raw fuel, and the black plugs could surely be a result of just running briefly several times.I love this car and I'm highly motivated to get it rolling again!
Jeff Lang