Can the air flow meter LNA1620AA be related or replaced with a after market part?

 

To know if your current one is alive it will read 1.2 volts DC at the proper idle speed , it will increase toward 5 on throttle up

This will be the middle wire of the MAF sensor connector , Green / Pink wire

It is feed 12 volts B + power unlike other engine sensors , Black / Light Green wire , there is a slice in the power feed wire that has the possibility to go bad limiting the current to properly run the MAF

The 3rd wire is a ground , Pink / Slate wire

 

Thank you for the information and diagram ,Hopefully I can figure the emissions problem out and keep my car on the road.

 

Check engine light codes ?

 

If you have a emission issue :

remove the exhaust manifold cover and inspect for cracks in the casting , causes rich unburnt mixture

under the car inspect the exhaust manifold donut gasket joint 4 down pointing studs are tight , 13 mm , may even need donut gasket replacement , Part # ?

Before the engine will go into closed loop regulation the coolant must reach 88 C

The instrument gauge is a different sensor and not accurate

See page 78 for the AJ16 SC engine

Codes are on page 111

801S TITLE (jagrepair.com)

With a ELM - 327 you should have :

Short term fuel trim both banks 0 %

Throttle position sensor 13 % at idle

Mass Air Flow at idle 5 grams / sec , there is a common software error

EGR error 0 % , you may not have a EGR in England

Engine coolant temp at least 88 C after warm up , there is a TSB to not rev the engine in a standstill environment and this may also apply to your SC engine version transmission , GM - 80E series