[mrtnmatheny]

Item one is a broken off bracket of sorts located on drivers side engine bay wheel well side. Item two is a small 12 inch rubber hose installed over a clear plastic one located adjacent to the windscreen washer reservoir . Presently not connected to anything travels straight down.
Auto no start. Have completed L=tronics except car running tests. Seems I may be down to looking into the 2 computers.

Cold start good but does not switch over to computer run scenario. Normal rest position for Red Baron

 

[ARwrench]

The broken off bracket looks like it was an aftermarket alarm horn/siren.

 

[sepehr]

The clear tube leads to the manifold vacuum sensor, which is located behind carpet, behind the passenger seat. The rubber hose should connect to a nipple on the intake plenum. Look at the rear off plenum under where the idle bypass and auxillary air hoses connect.

 

[sepehr]

Here (highlighted):

 

[spiderserie4]

as Sephr says...
leads to this gizmo

could be the sensor is defect (it starts to whistle), then it would be disconnected and the plenum nipple plugged up

 

[Scuderiazane]

Let us know if you get it sorted out...

 

[mrtnmatheny]

Removed mystery bracket. Found intake plenum nipple mentioned covered with rubber nipple. Is this a nonsense pickup not therefore needed? Tested spark plugs with a tester and getting same pulsing lite on all four. Awaiting noid lite to confirm results. Looks like the efc is next. Not sure at what point the ignition one is in use. Of course Hurricane Ian is delaying my journey with ECU Drs. Any other outfit out there recommended? Will keep eyes open for a standby ECU. Gee Whiz the price is 4 months allowance. Thanks all. Mort

 

[Scuderiazane]

Think the gizmo is post #5 is the altitude compensating sensor. Think it's only important for idle at high altitude.

Here's a troubleshooting guide if you don't already have one...

Bosch L-Jetronic Fuel Injection Tech Article

GREG'S BOSCH L-JETRONIC FUEL INJECTION IDLE ADJUSTMENT, DIAGNOSTIC AND TUNE UP PAGE. Bosch L-Jetronic is used on all Alfa Romeo GTV6s, Milanos, and 1982-1989 Spiders, BMW E12 5 series and 3 series cars, Datsun 280Z, 280ZX, All U.S. spec fuel injected Fiats and Lancias, 1984-1989 Nissan 300ZX...

hpsimotorsports.com

 

[mrtnmatheny]

Have completed the guide except for test requiring running engine

 

[sepehr]

The vacuum sensor is part of the ignition system. Without it, you don't get ignition advance - your car will be slightly slower and you will have worse fuel mileage.

The altitude sensor is completely different and part of the fuel injection system. L-Jetronic system does not control ignition. The ignition controller is a separate box.

You should hook up the vacuum sensor if it doesn't leak. If it's busted, cap off that hose, and the nipple on the plenum. Leaving the nipple open will leave you with a big vacuum leak and false air. Everything downstream of the air flow meter must be nicely sealed.

 

[mrtnmatheny]

Plenum input is capped. Will cap the line also just in case. Thanks for the info. Guess I should uncap first and see what I've got. Mort

 

[spiderserie4]

hook the vacuum sensor up (both ends) then drive the car
if you hear a whistle coming from the back of the cabin, then the sensor is bust.
cap it off again, enjoy driving....but the electric connector on the vac sensor needs to be connected, whether the vacuum hose is connected or not, whether the sensor is busted or not...

 

[mrtnmatheny]

Will have to wait for the enjoy part until I get pump computer checked out. Thanks again everyone. Mort