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Smog Check Repair

77 Cadillac Seville Can't Find New or Rebuilt Vacuum Advance Unit

Dear Sirs:

My 1977 Cadillac Seville Vacuum Advance has two ports. The vacuum advance is not working on my Cadillac Seville and therefore, it failed the CA smog test. I have called so many companies and parts stores across the USA for a 1977 Cadillac Seville Vacuum Advance with 2 ports to purchase with NO results. Can I have a 1978 Cad Seville Vacuum Advance installed with one port on my Cadillac?

Also, can I add a 'T' to the 1978 Cad Seville Vacuum Advance, so that it will pass your CA smog requirements? Presently, with one added 'T' it will not pass the CA Smog required 'Visual Test' for my 1977 Cad Seville Vacuum Advance.

Lastly, where can I purchase a new 1977 Cad Seville Vacuum Advance with two ports. Also, are their any 1977 Cad Seville Vacuum Advance companies that can rebuild my part?

Thank you very much for your efforts on this matter. I await your reply.




We recommend contacting the State Smog Check Parts Locator. The State's Part Locator might be able to help you find a new or rebuilt vacuum advance unit for your Cadillac. If the parts are not available, the state's smog check referees office (which runs the parts hotline) may be able to issue you a "Limited Parts Exemption".

Contact the State Smog Check Parts locator by calling (800) 622-7733. Also, modification to any of the vacuum lines will be considered a smog tamper. You'll need to keep the vacuum line configuration exactly as required by the manufacturer. Even installing a simple T-connector, will cause a smog check "visual" failure, so it's best not to reconfigure any of the vacuum lines. On a side note, have you checked Cadillac King in Lancaster, CA? They've got a ton of used Cadillacs on the lot. You might want to give them a call. If they've got the part, they can ship it to you. They sell parts world-wide. Take care and best of luck.

posted by SmogTips Support 06-08-2017 09:58 AM

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