Hi, holly. Code 12 is "system normal". It is displayed anytime you start checking for codes. Only means the computer is working and diagnostics are working. Code 34 is your trouble code: "Map sensor signal out of range, low". You probably need a new map sensor. Look for it possibly on the firewall, possibly a small rectangular black box with a 3 or 4 wire connector, and a vacuum hose attached. This sensor is critical for computer to know manifold pressure in the intake, so it can match fuel requirement to air for correct air-fuel mixture. If you can't find the Map sensor, have someone locate it for you. I don't think a new one would be very expensive.
Answers & Comments
Hi, holly. Code 12 is "system normal". It is displayed anytime you start checking for codes. Only means the computer is working and diagnostics are working.
Code 34 is your trouble code: "Map sensor signal out of range, low". You probably need a new map sensor. Look for it possibly on the firewall, possibly a small rectangular black box with a 3 or 4 wire connector, and a vacuum hose attached. This sensor is critical for computer to know manifold pressure in the intake, so it can match fuel requirement to air for correct air-fuel mixture. If you can't find the Map sensor, have someone locate it for you. I don't think a new one would be very expensive.