No, I have not thought about the O2's at all. I had the cat removed and have not done anything with the O2's ever.

How should it run with the O2 disconnected? Are you talking about how it runs after the 20min time period?

 

Does anyone else think it could be the O2's and not the opti?

How hard is it to replace the O2's?

 

dont know if this will help but here goes. i had a similar problem to this one on a different vehicle (not f body) but the symptoms were very close-fluctuating fuel pressure, air in lines. kicked my tech's butt. what we finally found is the fuel pump was recently replaced by the vehicle's owner and when he did, he didnt get the rubber hose fully onto the pump for at the sending unit assy, so it had some fuel pressure but also had air in the lines. i have luckily not had to change a fuel pump on an f body yet and i dont know if it is a similar setup, but they are both gm vehicle, so maybe its a possibility? you said it has hardly any mileage since the pump was replaced, right?

 

The pump was replaced about 30K miles ago, several years (maybe 6 yrs). The thing that gets me is the car runs great for about 20 min then it starts gradually at above 3800rpm's and works its way fairly quickly down to idle. It does act like its about to run out of gas but never does.

 

Well,what was the conclusion?Did you get this fixed?

 

after reading the first posted problem it sounds like the problem i had, if you cant find anything from the fuel pump to injectors wich i didnt, move to ignition, and i saw the post for the coil change which i did to, my problem was fixed when i changed plugs wires coil and opti sry if this dont make sense its my buddys b day and im drunk but just tryin to help

 

6speeding - Like you said, I didnt find anything wrong with the fuel system so Im moving on to the ignition. I have replaced the ICM and the coil with no luck and plan to replace the opti in the near future. I will post the results if I ever get it fixed.

 

I am also having a fuel issue similar in my 93 with an LT1. I had just bought the car the gas gauge is not reading correctly, one night she started sputtering like she was out of fuel and died. Now she is getting no fuel at all. Any suggestions would be a great help...

 

Generally not a good idea to "highjack" someone elses thread.

When you run out of fuel, it isn't unusual to damage the fuel pump and cause it to fail. Have you checked the pressure?

 

Just wanted to post the results in case someone else was having a similar problem.

I replaced the opti with a GM replacement from Summit. It actually was not that difficult of a job. This fixed my problem 100%.

Hope this helps!

Matt

Long live the optispark!!--cause if it dies its a lot of work to replace.