Our 1991 745 Turbo has begun to have brief moments when it hesitates or feels like I've lifted my foot when I haven't. My wife and I have noticed it happening once (not sure if it was the car or us that time) about 3 weeks or so ago, and then once earlier this week, then three times this afternoon going to the gas station. It was not empty, still had about 4 gallons in the tank.

I've got some experience with the 740 turbo and its quirks now, having been through the ECU Fuel Pump circuit failure, and new fuel pumps, so I have planned the following course of action and am asking you guys if there is anything else that it could be that I am overlooking, and what you think of my strategy. Also, below is what I have done over the past two years.

In the past two years I have replaced the ECU with a used unit to fix the ECU Fuel Pump Circuit problem.

Replaced both the main fuel pump with a Bosch unit, the fuel filter, the mesh "sock" on the little lift pump in the tank and then the little lift pump in the fuel tank. However, the main pump continues to make noise, kind of whining when running. I don't think this is normal and it concerns me.

My Plan:
I am going to install an over-ride switch on the fuel pump relay so that if the developing problem is the ECU Fuel Pump circuit failing all over again, we can over-ride that until we get a new ECU.

I am going to order a new radio supression relay tonight. Should have done that years ago, they are good to keep around.

Am going to also order in a new fuel filter, and main pump.

Sorry for the long post, but do you guys think I am on the right track, or could it be something that I am overlooking?

Thanks
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Scott Cook - 1991 745T, 1985 RX-7 GSL-SE, 1986 Toyota Tercel (Don't laugh, it is reliable, faithful AND gets 41 mpg!)