Bimmerfest - BMW Forums - View Single Post - If one boston is rare... (Passed smog today!)
View Single Post
Old 12-11-2010, 06:59 AM
drivinfaster's Avatar
drivinfaster drivinfaster is offline
Officially Welcomed to the 'Fest
Location: in the sticks you piney
Join Date: Nov 2007
Posts: 12,240
Mein Auto: rescued bmw's
Originally Posted by crisscross View Post
Does anyone know if intake air temp sensor would cause a missfire? I know def know it would cause a closed loop rich idle, and I guess that could cause a missfire?

no. i have not come across any instance where the air intake temp sensor caused a misfire. running rich would also not cause a miss. it would bog, run like poo, and co would be through the roof, not hc.

hc is a misfire indicator, so i would be looking faulty ignition (coil/plug/boot), or, if caused by a lean mis, faulty injector.

a cat would not cause a misfire, so i would not worry about that at this time.

find the cylinder that is missing and then do this. swap the coil with one cylinder, and the plug with another cylinder. see if the miss moves. if it does, then you have found the defective part. if it stays at the same cylinder, then you car going to be looking injector or valve issue.

good luck.

Reply With Quote