1972 911 Miss or Fuel Issue

[bahman]

My 1972 911E MFI, after sitting idle for a few weeks, has started a miss upon rapid acceleration. Gradual acceleration up to 7,000 RPM does not exhibit the miss. Accelerating from a cruise speed (any) does also exhibit this problem.

Fuel pump works fine, fuel filter is 6 months old, coil/points/rotor all check fine.

The car was running flawlessly before going into hibernation for the few weeks. I use branded fuel (Exxon, Shell, Chevron when I can find it) of proper octane, 87.

Any insight and suggestions would be most welcome.

[RSTarga]

Plugs, wires?

[bahman]

Originally Posted by RSTarga

Plugs, wires?

Plugs and wires are less than a year and 1,000 miles old. Will check them anyway. Thanks for your suggestion.

Bahman

[356911930]

Have you checked your fuel pressures? Do you have the fuel pressure fuel gauges? If not I would invest in some.

Rahl

[r lane]

Check everything before turning to the FI. Then as one respondent commented, check fuel pressure, 12-15 psi between filter and pump, check pump timing. I track MFI, and on a particular day, car wanted to stumble coming out of 5,7 and 10B at Road Atlanta. Felt like a carbureted car. Checked my plugs, one looked odd and found that that injector had lost its seal. Could no longer hold fuel pressure and was dribbling. Also I don't like Platinum plugs in a street MFI car. You didn't mention what you were running. Bob

[cmcfaul]

There is a screen connected to the fuel intake in the tank. Remove the fuel line from the tank and check the screen. It's prob gummed up, rusted, etc and limiting gas.

Chris
73 911 E