My 96 3.1turbo Diesel makes a buzzing sound after i turn the motor off, it is coming from something attached to the air cleaner. What is this and how do i fix it?
Vehicle: 1998 Isuzu Rodeo,with a 2001,2.5 turbo diesel motor,5 speed,inter-cooler,turned up fuel,adjusted waste gate for 14 psi of boost,air bags under front end with torsion bars ,2.5 exhaust straight thru sidepipe no muffler. 1949 Dodge 2 1/2 ton pumper fire truck, 15,000 original miles, with a 1991 Cummins 5.9 diesel, turned up fuel, 5 speed trans, two speed rear, also added P/S, P/B.
A definite buzz, all most sounds like a muffled horn, when i flick the ignition switch on and off a few times, it stops! Or if I just leave it stops after about a minute.It looks like some kind of electrical relay?
Last edited by rustymc on Tue Jul 13, 2010 8:19 am, edited 1 time in total.
I found it! It is some kind of fast idle vacuum relay, (part of the clean emissions system) if you block off the barb on the switch relay, it stops immediately - thanks any way. Russell