Went

This car has started nicely now for several months. I've changed the fuel filter, IAC, cleaned the throttle body, MAF sensor cleaned, changed plugs, cap and rotor and air cleaner. The timing was recently checked and set. Don't think I missed anything.
Yesterday...barely breath on the key and it fired up. I stopped to get gas today to top off the tank (we were driving from Hillsboro, OR south I-5 to Albany, west to Newport and back north along Hwy. 101 for a day trip.)
After gassing up, the engine died four/five times before running smoothly. I averaged 23ish MPG on the whole trip. Every time I shut down, it has taken longer for it to start. The idle sometimes pulsates at a low RPM. Never is it surging at a high RPM. Once it has started and idled OK, it goes like crazy if I stomp on the throttle. Once home I back probed the TPS. The closed throttle voltage is .54, WOT only 4.6v. What might I be missing? I had the car on Tom WOng's dyno a few months back and the checked the fuel pressure and it measured OK.
I checked and the car is not setting any codes, checked all the injectors resistance and they read all 16.9~17.1 Ohms.
I am puzzled about where to go next. Can't afford a big shop bill right now. Some suggestions would be appreciated.

Thanks, Went

Went

I disconnected the MAF sensor to see if it started any different. The car would start if I kept my foot on the throttle slightly. After running a couple minutes with my foot on the throttle, keeping idle around 700 RPM...it would idle by itself around 500 RPM. After reconnecting the MAF, starting and idle was the same as when disconnected.

Went

Cliff Harris

Check to make sure the fuel pump is running for 2 seconds when you turn on the ignition. If not, then the fuel pump relay might be bad.

To check the fuel pump relay: Disconnect the oil pressure switch. If the car won't start after you do that then your fuel pump relay (or the connections to it) is bad.

Went

Wouldn't the relay being bad set a code? The car did start this morning as it does after disconnecting the oil pressure connector.

Went

DanielRicany

No. Is this car all stock? Did you use a different octane or a different amount of ethanol in the gas that you filled up with?

Went

My Vette is stone stock. I have always used premium gas (well once I used a mid grade because I was broke at the time...) Usually the car gets Chevron or 76. This last time it was Shell premium. This summer I had a corroded coolant temp. sensor connector. That was replaced...maybe the sensor should be too.

Went

Went

So, the car is running normal once again. I had changed the IAC, reset the counts(correct term?), ended up replacing the fuel pump relay and checking vacuum hose connections and some connectors. Pulled CTS, TPS connectors cleaned, applied dielectric grease. One vacuum hose needed some help. Runs nice! Going today to get some "nearly" straight pipes in place of the mufflers.

Thanks, Went