I have a 2002 Sierra 4.3l that won't go over 25mph. Do you think it's due to a bad EGR or catalytic converters?

Answer

Decreased engine performance is more commonly associated with a clogged up cat in this case. You can try loosening the header exhaust pipe and see if this improves power. Also, check your computer for codes. If there's a problem in the transmission, the vehicle might be operating in 'limp mode.'

Updated on April 9, 2018

Original Article:

Symptoms of a Bad EGR Valve
By Dan Ferrell
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