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Hey all I have a stock 1993 Corvette I've purchased as a project and have been able to get quite a long ways but have hit a wall with this one last issue.
Little background on the vehicle and the parts that have been replaced so far:
Its a stock 93 Corvette 5.7 LT1 with 95k miles that did not run when I picked it up, it cranked but wouldn't start.
-Found the Ignition Control Module and coil were bad, replaced both now it would start but ran rough with a bad misfire
-Inspected the plugs and wires, they looked original, so plugs and wires were replaced. Found two cracked plugs in the process
-when changing plugs found that the O2 sensor wires were lying on the exhaust and partially melted so it got two new O2 sensors
-Ran better now, but still had a slight miss, a few of the injectors didn't look correct when viewing with oscilloscope, checked their ohm against recommended and found the injectors weren't in spec so it got new injectors and a fuel filter
-Map sensor and seal replaced due to being out of spec from factory ranges
Now we're at the current state. For the most part the car runs fairly well 90% of the time once it gets moving. The problem is when taking off from a dead stop or occasionally when downshifting to pass on the highway, it will completely fall on its face like you've momentarily cut off the fuel. It will buck, stutter, backfire/pop and will eventually die if you keep trying to accelerate. If you let off accelerator and try again it will take off as if nothing happened 2 seconds ago. Once you get up and moving it typically runs fine until you stop again.
I do have DataCAT and have taken several logs of when the issue occurs. I can export the data to excel or just post up a datalog file if anyone wanted to look at it.
I'm at a loss on where to even continue checking at this point. I haven't been able to find any vacuum leaks and can't replicate the issue in neutral/park, only when loaded and actually trying to take off.....sometimes. Fuel pressure is solid when idling and raises as expected when the fuel pressure regulator vacuum line removed. The one thing I haven't been able to test is what is the fuel pressure doing when the problem occurs as my hose isn't long enough to tape on the windshield and drive around.
Edited to mention: there are no codes stored
Any help or suggestions on where to go next would be much appreciated. I feel like I've hit a brick wall with this issue now and can't find my path forward.
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