1987 Jaguar XJ6 Starting problem

I drove this car from 1987, with no problems. I had a minor accident, front end damage, minor body work and radiator repair. Car was still running after impact. I shut it off, and when I restated, it turned over for a long time before it started. It had done this ever since, and never before. Maybe 20 to 25 seconds before it starts. I keep the starter going with my foot off the accelater. If it start. But not quite, I turn the key off, and when I try again, it will start immediatelyt. Then it runs fine, just a little engine wabble. Yesterday in the morning, it would not start at all. I quite trying to save the battery. The weather was fine, about 70 F. It did this once before, but started in the afternoon. Not today. Any suggestions?