hi everyone I'm new to this forum and looking for some help with my 99 Lumina with 3.1 engine. issue that I'm having is that I have a extremely rough idle. I don't have any misfire codes but just a EGR Valve open code. in order to keep the engine running I have to unplug the MAF sensor. I checked to see if I had any dead cylinders and I'm getting spark on all the cylinders. when I unplugged 1,3 and 6 engine died out. cylinders 2,4 and 5 had no affect when unplugged. but like a said I have spark on all the cylinders. I also have the oil pressure switch light on that come on when this all started. I replaced the crankshaft sensor no difference. thanks for any insight.

 

First , find out what is going on with the oil lite ? If you really do not have oil , the rest does not matter .


I would check the oil level & then either change the oil & filter , or at least change the filter & top off the oil . ( Is the oil filter stopped up or defective ? )


See if the oil pressure sensor & wiring ( including connector ) is OK .


Did you hear any knocking , clicking or tapping ( lifters ) ?


You get these straightened out , come back with an update .


God bless
Wyr