I recently purchased a 2005 31' Tiffin Allegro with the 496 Workhorse Vortec motor with a Banks header exhaust system installed. It was running rich at the time, I replaced the plugs, wires and heat shields.

It still idles rich and is diesel like rich under load. I cannot see any O2 sensors in the system and hear rumors about a Mass Air Sensor that may be the issue. I don 't know where it is located, the part no., etc.

Until I can locate a motor manual for this motor, can anybody pass along any ideas?

There are no OBD codes or engine light showing.


Thanks!

 

My problem is solved, I cleaned the MAF and replaced both O2 sensors. Whichever one was the culprit I don't know, but I'm good.