My 356 4 cam is sputtering and back firing like it's not getting enough gas

Asked by Mar 30, 2014 at 02:23 PM about the 1957 Porsche 356 A Speedster

Question type: Maintenance & Repair

My newly rebuilt 4 cam has been running great and it just started missing and back firing
and sounds like it's not getting enough gas or it got some bad gas....sounds terrible.
Modes anyone have any suggestions?

3 Answers


Recheck your valve settings.

1 people found this helpful.

Could be something simple like a blocked fuel filter, a kink in the fuel line or intermittent fuel pump?

Best Answer Mark helpful

You said it was recently rebuilt and it ran good. It could be any of Andy's suggestions, all of which are easy to check. Valve clearance is critical, and if off, it will run rough. Do your checks, maybe check to see if the plugs are fouled, plug wires are in good shape and not grounding, and check to see that the distributor is not loose, use a timing light and maybe add some fresh gas. All common checks. Good luck

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