Having problems with your 1998 GMC Sierra ?
I know What the codes mean and how about going to fix them but will that also cure the high idle speed of 1600 rpm in neutral also the hose that goes from the air intake to the passenger side valve co
\015 What could be causing the high idle speed of my 1998 GMC Sierra 1500 5.7 liter also have codes P0440 and P1345\015
Could be your tps sensor needs to be adjusted or a vacum leak(intake maybe)
Repair Help & Product Troubleshooting for 1998 GMC Sierra
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