'92 E34 Calif. Smog Failure

[BlackOnBlack]

Hey all.
Another Calif Smog casualty.
I've had the car for 9 years and it's passed smog on the first try only once.
It had a valve job about 4 years ago at 223K and I replaced the fuel pump in 2013.
And just recently I replaced plugs and O2 sensor, changed the oil and I run Chevron Supreme in it.
@255K miles;
The two things that are present are:
- occasional high idle when stopped. The IAC was replaced when the valve job got done.
- occasional pinging going through @ 2500 rpm.
I checked for codes but only got the 1444.

See the attachment for the ugly results...gross polluter...NOx at low speed was 2161 with a max allowed of 762;

The guy that tested it pointed me in the direction of the Air flow meter and Throttle body sensor.
Also mentioned perhaps leaking injectors.

I know it's a long shot but does anyone have any ideas? I just wanted to have some ideas before
I bring it to different mechanic on Wednesday for diagnosis.
Thanks,
Steve

[genphreak]

Clean the throttle body butterfly. Check the ICV piping, particulalrly the connectors into the intake manifold. Up behind the TB, where the sun don't shine and monkey hands have trouble going where no rat has been before.

Also the Viton ring on the PCV pipe that goes out to the Charcoal canister, it can go bad where it enters the VANOS rocker cover. Check the exhaust has no leaks, esp upstream of the cats, andbtw it has a MAF not an AFM. The MAFs tend to go wrong sometimes, perhaps try another if unsure.