After getting some "bad cheap fuel" a few weeks back in my 2001 chev s10, with a 4.3 v6, now I have a long cranking before it starts. The crank sensor was replaced and the crank sensor relearn was done. It still throws a code of a misfire, sometimes a code of multiple misfires. it runs fine one it starts, but at highway speeds it will throw the code on the dash, yet still run fine. I dont know if the spider is clogged or the fuel pump strainers, are clogged. I have fuel pressure and it maintains it, on the guage. It almost sounds like the timing is off a bit.
long cranking before starting, poor fuel mileage, 160k miles. tuned up at 146k.
The engine always started on the first crank. No it cranks for 5-10 seconds
before it slowly starts.
Try running some iysoprofel (like red bottle of heat...NOT the yellow bottle) threw a couple of tanks of gas. Wouldn't hurt to change the fuel filter and then do a bleed down test with a fuel pressure gauge to see if there are any indications of a leaking regulator, spider lines, and or injectors. If you find any one of them are leaking it is recommended to replace all as a unit.
Multiple miss fires would be in the fuel, unless there is something wrong with the spark plugs, wires, or coils.
thank you,...the fuel and air filters were just changed with 20k miles on each. the air filter was dusty at best, and no dark dirty gas came out from the inline gas filter. I checked under the distributor cap today for any moisture, oil, etc, but it was dry as dust. I have been adding fuel injector additives since this happened, but no real change. The fuel pressure, with the engine off, stayed steady, observing for a few minutes on the gauge. I have the intermittent fuel gauge reading issue, but never had a fuel pump issue, possible clogged strainers,  at the fuel pimp, till now. Replacing the fuel pump would eliminate both those issues, but might not be needed, if its the spider or just a fuel issue that will hopefully clear out after a few tanks of fuel. thank you for your response.
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