Calif Smog Help Please

[jpdriver1]

Well for the third time the 89 has failed smog -- 

 

15 mph readings;

O2 3.3

HC 7

CO 0.00

NOX 1866 gross polluter level is 1800

 

25 mph reading;

O2 1.0

HC 2

CO 0.00

NOX 538

 

Items replaced to date;

plugs, rotor, dist cap, air filter, catalytic converter, egr valve, O2 sensor (bosch), fuel pressure regulator, fuel filter

vacuum lines all checked/routed properly 

 

bottle of chevron "guarantee to pass" stuff run through it 

 

currently has 91 octane fuel in it

 

temp reading is just over the first line all the time

 

mileage is 169,000

 

open cooling system, 3 row radiator --- three months since change over

 

running too cool maybe?  

 

I've run out of ideas 

[airspeed]

Your temp gauge may not be accurate but those engines need a minimum temp or 195 and I believe the ideal temp is 210.

[jpdriver1]

too true -- it has a new stock stat in it --- thanks 

[gogmorgo]

I'm not an expert in emissions testing in any way, but I'm curious as to why you're running 91 octane. If your engine isn't tuned for it, it's not going to improve anything. If anything, it might make things worse because it doesn't ignite as easily as lower octane.

I've heard a few people recommend bombing down a freeway for 10-15 minutes, some say in a lower gear than normal, to get the cat good and hot. Might help reduce NOx.

[jpdriver1]

thanks gogmorgo --- the hi test was put in by mistake -- burning it out as I go along --- 

 

update --

 

EGR & EGR solenoid valve tested per haynes manual -- both correct

fuel pressure 28 w/vacuum & 32 w/o

[cruiser54]

thanks gogmorgo --- the hi test was put in by mistake -- burning it out as I go along --- 

 

update --

 

EGR & EGR solenoid valve tested per haynes manual -- both correct

fuel pressure 28 w/vacuum & 32 w/o

Should be 31 and 39.

 

What brand of stat? 

 

I don't like Bosch O2 sensors. NTK is good.

[jpdriver1]

autozone duralast

 

changing out the o2 sensor for denso tomorrow