My car had the intake gaskets replaced. I put it back together. A couple bolts in the upper intake and throttle body. Also has broken vacuum hose for the fuel pressure regulator and the canister purge valve. Now it runs rough and puffs smoke that smells like gas. And I have to apply the gas to keep it running. What can cause this?
I would start by re-checking your work. Repair any vacuum leaks. Repair the vacuum leak at the fuel pressure regulator. Check to see if the intake gasket is still leaking. Just because the gasket was replaced doesn’t mean it was done right.
If the check engine light is on, check the codes and post them below in the comments. The codes will help point us in the right direction.
Lower Intake Manifold Replacement – 2001 Chevy Impala
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