Did you figure it out?
My car (92 4dr LX-stock) didn't start after a half hour drive and two minute park last week, I reached up and tapped the main relay. It started and worked fine for a few days.
The while driving, I get the same code. I cleared the code by removing the fuse and haven't had it come back, yet.
Mine has the original relay and pump with 360,000 miles. If you figure it out please post back diagnosis and results.