[V8] hard starting sometimes and fluctuating idle

[getur at optonline.net]

I looked through the knowledge base and tried using the search function but couldn't come up with anything definitive about the problem that has started occurring with my V8.

Over the past week whenever I start the car up it takes a little longer to start and when it does for the first 3 to 5 seconds the idle fluctuates from around 300 to 800 rpm. It then steadies out and I have no further problem with the idle. In addition a couple of times the car stalled out on the startup and I had to crank it for about 5 to 10 seconds for it to restart.

My thoughts are that it could be the ISV, but if it's that then I would think the idle would jump around whenever I'm at a standstill and it doesn't. The other item that might be the culprit is the FPR. But, I would think that that would only cause a problem if the car had been sitting for a long time, say overnight. Last night though I had a hard time starting it after it had sat for only an hour. It took 4 tries to start it and the rpm was very low once it did start, but then jumped up after about 5 seconds of running. Which brings me to the last item which is the crank sensor. I believe the car needs this sensor to start and if its problematical and gets heat soaked it would cause a hard start problem.

Any suggestions or btdt for this problem?

George Tur
91 V8