Suburban Sputtering Uphill

chevrolet
suburban

#1

My 1999 Suburban K1500 is sputtering uphill. Already replaced: fuel filter, air filter, plugs, wires, pcv, distributor. This took care of engine misfire codes. No error codes for the last two months, but it’s a lousy ride uphill on the highway at 20mph. O2 sensors next?


#2

Check fuel pressure. There should be a fitting on the fuel rail…


#3

If the fuel pressure is correct you might also consider the possibility of clogged converters amd this could be caused by age and poor running.

This can be easily checked with a vacuum gauge.