It has what seems to be a vacum leak but all hoses are on.it dies at low idel. Unable to drive engine dice when put in gear. Possible MAP where it where it is.
GMC Q&AAsk Your Question
1991 GMC Vandura 2500 Question: Engine starts but runs erotic and will not idle, it has what seems to be a vacu
Answer #1goodguy August 21, 2013, 19:10Master
check the throttle body gasket
Answer #2pushrod August 22, 2013, 01:05Master
SCAN TEST, (IAC). Light on? Any vacuum leak at or around the throttle body, especially the gasket, will result in very high idle speed!!! Have the idle air control checked with a scanner!
Answer #3Greg's Orange Auto (12184 Answers) , Orange, CA - (714) 361-9386globalhelper August 22, 2013, 05:40Master
agree with goodguy