Could be vacuum leak check All the hoses, check for cracks in the intake manifold, bolts loose, gasket sucked in, air entering the exhaust ahead of the OX sensors is all detected by the OX sensors and try to richen up fuel injected but can only go so far in corrections.
This goes to the point the motor runs rough from leaness in and not enough fuel to counter the leaness.
There are different procedures to use for leak detection. Some use propane, some use smoke, some use a scanner to watch certain sensor reactions to forced test procedures.
Monday, December 19th, 2011 AT 8:17 PM