Hi guys,
Well as luck would have it my 2 year smogtest has rolled around again,and the panic has set in again. My 1986 740 GLE non turbo ,has 225K miles runs very well
no abnormal idle or poor running condtions,but its fuel milege has dropped within the past few months to under 20 on the highway,Ive cleaned the throttle body and replaced all the seals ,replaced the intake manifold gasket,when I did the fuel injection water temp sensor 2 years ago to pass the last emissions test,Ive got new plugs and cap and wires within the last year,I wondering if my fuel pressure regulator and cat convertor may be the concerns,being as they are the only 2 remaining units that have 225k miles on them ,Ive changed the O2 sensor about 2 months ago,in an attempt to pickup mpg to no avail, the pretest readings on the HC 186 ppm , I need to be under 120 ppm to pass at the idle test
because of the ZF tranny,as always thankyou kindly in advance,I would really like to keep driving the car,PS my flame trap and oil seperator are both new,like I said the vehicle runs very well? Thanks Ray