dasouthwon

I have an 87' corvette with 150k miles. In the last 500 miles I've replaced the fuel pump with a 255lph, fuel pump relay, fuel filter, plugs, wires, dist cap & rotor, and coil. Over the last few days it started this wierd problem of the rpms slowly dropping until it died. Slapped on the fuel pressure gauge and noticed that my fuel pressure at start up was roughly 20 psi. It would hold this pressure for a few minutes then slowly start to drop until it hit 0 and the car died. This afternoon I put a new fuel pressure regulator on, hooked up the fuel pressure gauge and cranked it up. Fuel pressure gauge shows around 33 psi at idle, which from what I understand is about 10 psi too low. Im kinda stumped as too why I'm not at least over 40 psi. Any ideas or suggs would be greatly appreciated, thanks, Brian

george 88gta

iTrader: (1)

Did you have the vacuum line , to the regulator, disconnected? If not, then 33 is a bit low, but not bad. You should see 42+ psi with the vacuum disconnected. There is a process, in the shop manual, to diagnose fuel pressure problems. Basically what you do is clamp off the lines to see if th epressure drop stops. Done with the engine off. One quick test is to attach the gauge, turn the key on, then off and watch the fuel pressure. It should take at least 10 minutes for the pressure to drop off.

dasouthwon

well the car ran great until it was time to come home from work today and the problem returned. It got progressively worse until I could only make it about a 1/4 mile before it would die and I had to shut it off and let it sit for a couple of minutes before I could recrank it and drive another 1/4 mile. I noticed my voltage started dropping and was down to about 13.2 volts by the time I got home. Is all of this due to a failing alternator? I've pretty much replaced the entire fuel delivery system except for the injectors. Fixed all the vacuum leaks. Don't know what to do next. I'm headed to get another alternator.