Q: After replacing valve cover gaskets, car runs horrible, and throws 5 different codes.

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I did a cam cover gasket job on my 2003 cadillac cts with the natural aspirated 3.2l engine. It seems sealed up fine now, used to leak oil on the exhaust manifolds, stunk, and smoked worse and worse over time. Everything is back together, but it runs terrible. I get 5 check engine codes: P1779, P1791, P2105, P2123, P0700. I didn't have any codes before I started this job. All the vacuum lines appear reinstalled correctly, all the connectors seem OK at least on the outside. Wondering if I have a broken wire on a connector, and which one that might be. The two big connectors to the ECM were off, I haven't checked to see if I might have a bent pen. . Hoping someone out there in car mechanic land might have an idea of where/what to check next.

My car has 152000 miles.
My car has an automatic transmission.

Hi there. Look on the engine for any ground wires. There could have been a ground wire that was disconnected to remove the valve covers causing all of the codes to appear. A ground that is not hook up can cause electrical components to fail and not function. If you need further assistance with your check engine light being on, then seek out a professional, such as one from Your Mechanic, to help you.

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