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Question: Stalling Engine

I purchased a used SC430 with 95,000 miles about a year ago. Soon afterward, it began to stall, similar to vapor lock, during acceleration and even with steady driving. It also stalls occasionally upon initial start from a stop. This has continued, regardless of weather, and it is intermittent. I have found that it can be overcome by releasing the gas pedal for a few seconds, then depressing it again. The stalling has never caused the engine to stop completely and idle is fine at all times. I would say the frequency of this hesitation averages about six times for a 20 minute drive.

My wife recently drove it to our new home. I forgot to mention the stalling to her, and she said it caused her to drive quite some distance at 45 mph even with the accelerator almost floored. I suggested taking her foot off of the accelerator for a few seconds, and this also worked for her. I had thought it might be a fuel filter, but I understand these are almost lifetime filters, can be difficult to change, and we have only 97,000 miles on the vehicle at this time.

I have tried different fuel octanes and used a can of water remover, all with no change to the stalling. I would very much appreciate suggestions on what might cause this and how to remedy it.

Haven't had stalling for about a month, but have driven it very little. Doubt that the problem has resolved itself.