My 95 has an intermittent problem. It will crank fine, just not start. Fuel pressure is okay (about 43 psi) and I have a spark. Put a new coil in just for fun, still didn’t start. As it cranks it occasionally tries to start. After I crank repeatedly and for a very very long time, it will start, run rough for about 10 seconds, backfire through the exhaust, and then run fine. Everything will be fine for a week or two. Then it doesn’t start again. And I go through the same routine. Acts like it is flooded. Any ideas?

Seams to be associated with how long the car sits. Although I’m really not sure about that. I do known that the only time it does it is after it has at least set over night.

I’ve checked fuel pressure drop, here’s the data. Key on to pressurize system. Key off. Pressure 43 psi. Then at 2 minutes, 42. At 4 min. 40. At 6 min. 39. At 8 min. 38. At 10 min. 37. At 12 min. 35. At 15 min. 35. At 20 min. 30. At 30 min. 26. At 40 min. 24. At 50 min. 21. At 60 min. 20. At 90 min. still 20. At 110 min. 16. At 120 min. 15.

Is that normal?

 

I have a 97SS with a supercharger and had similar sporadic hard starts. It was a engine temperature sensor that was shorting and causing the computer to read the engine temp at -5 degrees.

Hope this may help.