F.I. Hesitation

[fiatfreak]

My '69 fuel injected 124 Spider (L-Jetronic 1800) has developed a sporadic hesitation. It feels like a fuel delivery issue rather than ignition. It’s not a complete cut-out but more of a power loss. It losses power under load, almost like a car with vapor lock or a dirty filter. It does it for no apparent reason. Sometimes when the car is cold, sometimes after it's warmed up. It will run fine for several days and then start acting up again.

I pulled the tank sender and verified that the tank is clean and the pickup screen is not clogged. I replaced the filter too. Any ideas?

Mark

[ClarkTheShark]

hesistation? on acceleration? on wide open throttle? completely sporadic? sounds like fuel youre right.

[htchevyii]

Mine acted similar to that when the AFM flap was stickng.

[fiatfreak]

I changed the AFM but haven't driven it yet. We'll see if it made a difference. I post when I get it fixed.