89 Bonneville won't start

Hi, Just joined this forum and searched the Bonneville threads for my problem. Found similar threads to mine except I can't find anything wrong with mine. Here's how it happened: It acted up intermittently on the highway. It would hesitate for about a second every few miles (just as if I shifted the gearshift into neutral while keeping my foot on the gas pedal). When it happened, the speedometer needle would suddenly drop and the "service engine soon" light would blink then go out and the speedometer would suddenly jump back up again. It did this several times then the light came on; the speedometer suddenly dropped to 0 and the engine stalled and refused to start. I had it towed home (about 5 miles) and the odometer never moved. A few hours later it started and worked perfectly. Next day it still worked, so I drove it and after a few miles it quit again. Now it won't start anymore. It's a 3.8L V6 with 275000 Km. Here's what I noticed and checked: Fuel pump won't make any noise when the ignition is turned on, but works after I try and start it. Fuel pressure is 47 psi. All 6 spark plug wires give off a healthy spark at the plugs and the plugs are dry. I substituted both the ignition coil pack and ignition module with known good ones. "Service engine soon" light won't light up anymore. I bought a code reader and it won't read anything; not even code #12. All fuses are good both on the driver's side fuse panel and on the fuse/relay panel next to the computer. I also substituted a known good computer. Any suggestions?

check ground wires under the coil pack right behind the ground cable

Hi, I checked the ground wires as you mentioned and sure enough, they were corroded. I took the wires off the bolt, cleaned them up and reinstalled them. Now the car works perfectly. Thanks for the fast reply and great advice!!!

thank you for posting the fix

Have a peek at that fuel pressure. 47 psi is a bit high. Possibly your fuel regulator (on the fuel rail on the engine, by the return line) is stuck.

I checked the fuel pressure again. I am getting 38 PSI with the engine running .