98 l29 454 mystery

Lennyobs said:

when I pull out plug wire #1 & #8 no change in idle or revved above 1000rpm.

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Supercharged111 said:

Like I said, don't overlook the possibility of 2 junk injectors. Did you have a chance to see how it ran before you put it in your truck?

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Schurkey said:

Obvious question: are #1 and #8 plug wires swapped at the cap?

If you moved the injectors and the miss didn't follow the injectors, it's not the injectors. DO YOU HAVE POWER/GROUND at the #1 and #8 injector harness? Will it light a 'noid light?

Do you have appropriate cranking compression pressure?

Have you popped a valve cover to see that the valves are opening/closing?

Will your #1 and #8 spark plug wires fire an HEI-calibrated spark tester?

Spark plugs on those two cylinder fouled? Cracked? Not gapped properly? I bought a '97 K2500 with L29; had a dead miss in #8. Also had a transmission that wouldn't engage the converter clutch. I figured I'd be spending real money to fix the engine and the trans. Turns out that I had a broken (cracked) spark plug. Stuffing in a single spark plug fixed the misfire, AND the computer won't engage the converter clutch if a misfire is detected--so the spark plug "fixed" my transmission, too.

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Lennyobs said:

I’m guessing that injector wiring for 96 vs 98 is a bit different for inj1 and inj8

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Lennyobs said:

I’m guessing that injector wiring for 96 vs 98 is a bit different for inj1 and inj8

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rpoL98 said:

another difference might be the early fuel evaporation thing, something bout a sensor in the gas tank. i remember looking at that, and that it was the no-go deciding factor for me. years ago.

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