Your coils are potted in the cassettes. When you had the cassettes off, that yellowish compound in the 4 recesses is the epoxy compound. No way to get to the individual coils unless you again remove the cassettes and pull the ICM out of each one and try some pin resistance checks.
In a lot of these responses, I recommend checking and or just replacing the coil boots. Cheap insurance. Make sure the cassette ground spring is doing its job.
Other causes of a P0300 (stall detected) are vacuum leaks and intake manifold connector plenum cracks and impending CKP (CranKshaft Position sensor) failures.....but those will usually also set P0171, P0174, P0335/6, and P0385/6 codes.
(EDIT.........If, as you posted down in another thread, you suspect the coil cassette(s), take a look at your car parts, ignition, in www.rockauto.com. They still have a few of the OEM DELPHI cassettes with ICM for under $200 apiece.)
For someone with a late FWD Northstar engine without plug wires, here's what we're talking about:
In a lot of these responses, I recommend checking and or just replacing the coil boots. Cheap insurance. Make sure the cassette ground spring is doing its job.
Other causes of a P0300 (stall detected) are vacuum leaks and intake manifold connector plenum cracks and impending CKP (CranKshaft Position sensor) failures.....but those will usually also set P0171, P0174, P0335/6, and P0385/6 codes.
(EDIT.........If, as you posted down in another thread, you suspect the coil cassette(s), take a look at your car parts, ignition, in www.rockauto.com. They still have a few of the OEM DELPHI cassettes with ICM for under $200 apiece.)
For someone with a late FWD Northstar engine without plug wires, here's what we're talking about:
