Hey im new on this forum and i have a 1997 GMC Jimmy, it runs fine but whenever i start it cold, it turns over right away. After its warmed up if i try to start it it takes a few seconds and i have to pump the gas to get it going, kinda idles rough amd once bogged after accelerating from a light. Any thoughts? Maybe clogged catalytic converter, bad plugs/wires or fuel filter gummed? Thanks all help appreciated My 97 jimmy

 

A non tool test for a clogged cat is applying power as you go up hill. If it bogs down or seems to lose power that can indicate a clogged cat/exhaust. Also, you would probably have a code of P0420. If you want to properly check back pressure on your exhaust you can a loaner gauge for this purpose from an auto parts store. A vacuum gauge will also work that displays low psi pressures as well as vacuum. Remove either of the front O2 sensors and install the gauge. You should not read higher than 1 psi of pressure. I would also suggest that you conduct a fuel pressure/leakdown test. You can find an excellent post from Captain Hook in my signature block.

 

A failing ECT sensor will cause hard starts and performance issues when warmed up. You can test the sensor with a DMM. Here is a chart of what it should read at various temps. Is your temp gauge reading accurately? When fully warmed up it should read around 240-250 ohms. Cold - look at the chart. If it is really high resistance when cold, like 100,000 ohms it's bad.

 

Side note, does your basket have the extension on it? Does it cover the entire roof rack?

 

Yeah its got an extension, pretty much covers the whole roof

 

i sit around 100c warmed up fully
smells pretty rich from the exhaust though

 

thanks, ill be replacing my distributer aswell as spark plugs and wires and probably straight pipe from headers back and see if it changes it smells super rich lately