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Engine issues?

I’m having issues with my 98 k1500 5.7L Vortec where it is sputtering and when I’m accelerating down the road and sitting in idle I’ve replaced everything in ignition and just replaced the EGR valve. Video is linked below for idle sound. https://share.icloud.com/photos/024WnzvIe0eHo0aMmdRXQ-SYw#Coldwater,_MI

You’re going to have to find another way of uploading that file so we can hear it, Youtube or something similar.

Nobody here is going to download a file onto their computer from an unknown person to listen to it.

I too passed on the down load.

yosemite

yeah, not downloading…

but:
have you checked your fuel system? fuel filter, fuel pressure?
is check engine light on?

define “everything” in “I’ve replaced everything in ignition”

I have replaced within the last year: spark plugs and wires, ignition coil, cap and rotor, starter, alternator, EGR valve, new fuel tank and pump, brake lines are all new, pads and caliper, and just finished redoing my pinions in my differential.

You asked for a YouTube upload

Sounds like a leaking exhaust system to me, which will mess with the O2 sensors and cause improper fuel mixture.

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Is the check engine light on? If so, what codes are showing? Those trucks had issues with the plastic intake manifold cracking. This usually results in a coolant leak, but I suppose could result in a vacuum leak that could cause rough running.

More likely, those trucks had issues with the fuel injection assembly in the manifold. It’s often referred to as the “spider” assembly. I don’t know how to check to see if that’s the issue though. Might google problems with “spider” injection assembly - vortec engine and see if you find anything that looks like your problem.

No codes or check engine light on

As far as the exhaust leak and O2 sensor I’ve just ordered a new kit and will update after Christmas.

I’d start w/these three below assuming no codes and you are certain you have healthy sparks at all spark plugs. If any doubt about the ignition system situation, look at the engine idling in the dark, see if you see any sparks flying around in the engine compartment.

  • compression test
  • fuel pressure test
  • verify ignition advance is working

If your engine uses that spider ass’y those seem to be really common problem sources.