Acceleration Hesitation

[MacGyver]

Hello,

I have a 1987 300E with about 195K miles. Purchased used last summer with no records. I have a problem with a hesitation, sometimes a small backfire in the engine, only when accelerating from a stop. If I accelerate when the car has any momentum, there's no problem. It's not terrible, but it bugs me as I believe there should be no hesitation on a good running engine. I've replaced: Plugs, Wires, Cap, Rotor, Injectors, OVP. Each part replaced seems to have improved it a little, but it's still there, and I'm getting frusterated. The hesitation doesn't seem to happen when the engine is cold.

Also, the SRS light has started to illuminate...it started when I was moving from FL to NC during the drive it was intermittent. Now it stays on for about 10-15 seconds after engine start.

My questions are: What causes the SRS light to illuminate?
What should be my next move in trying to diagnose the cause of the hesitation?
Could the two be related in any way? (Someone suggested that a bad OVP relay could cause both to occur.)

Thanks for any answers and/or advice!!!
TC