I have 98 GMC Sierra 1500 RWD with 4.3 L engine and automatic transmission.
Have replaced the following within this year:
- distributor cap
- spark plugs and wires
- valve cover gaskets
- thermostat and radiator flush
- oil change and filter, and fuel filter as of yesterday.
Problem started out of no where hesitation, sputtering and rough like mild clogging and progressively getting worse. NO CHECK ENGINE LIGHT AT ALL DURING THIS TIME STILL.
Things that I had planned to get done in next 2 weeks before this:
- Intake manifold gaskets (both upper and lower)
It's been suggested to double check spark plugs, wires settings and connection to distributor cap. Distributor cap under warranty from shop that did job so told don't touch it.
Now can anyone give me any suggestions as to what else to look at or for? Really, this truck's engine has less than 85000 miles on it (3rd engine) and almost all components have been replaced or serviced. At a loss here and need help figuring out what it could be so I can fix it or get a shop to fix it.