1989 Riviera MAF sensor code E034

[Data.Doggg]

First of all, thank you to everyone that posts questions and answers. There is a tremendous wealth of information here. This is invaluable to an amateur car hack like me. I was able to locate all of the information I needed in the Buick forums. So I am here to add to the body of knowledge just in case there is someone in a similar situation, and that is why this thread title is so specific.

My wife’s daily driver is a 1989 Riviera (3.8L VIN C) that we have owned for about a year. It recently began hesitating, surging, idling rough, and stalling. The SES light was on steady and there was an active E034 (no MAF signal for over 4 seconds while engine running) and E034 history. My course of action:

• Searched the Buick forums for threads about MAF sensors and similar drivability issues.
• Cleaned the MAF sensor with MAF sensor cleaner.
• Visually inspected the MAF sensor (no obvious external damage).
• Installed a new air filter.
• Replaced the sensor and took a test drive (no active codes, but drivability issues remained along with an intermittent SES).
• Checked for vacuum leaks (found none).
• Removed the MAF sensor and cleaned the housing.
• Cleaned the throttle body.
• Cleaned chassis and engine grounds (just because I always do).
• Put everything back together and took several test drives (no codes, no SES, and no drivability issues).

It turns out that the MAF sensor code was pointing me to overdue maintenance from the air filter to the throttle body. Now I wonder what other maintenance may have been deferred by the previous owner. Other than time the total cost was about $15, which includes a new toothbrush (mine was sacrificed for the greater good). 😎