1974 1.8L engine fast idle then stalls, Fuel injection issues Options

[tshih914]

My 1.8L 914-4 with stock Bosch L?-Jetronic FI after being stored several years started to develop a hard to start problem. When finally started would stall when I give the gas pedal any input to raise the revs. I suspect there was some kind of intake air leak and while fiddling around had a backfire which blew the AF meter which I had Pelicanparts repaired. After replacing the fuel lines with the stainless ones from Tangerine Racing and flushing out the fuel system with Techron the engine started to run normally for a short time. Now the engine can be started and fast idles at 3000 rpm but again any input to rev up the engine results in stalling. The idle adjustment screw at the base of the throttle housing is fully closed. Any suggestions on how to fix?

[Van B]

Whatever you have back there by the batter near where the decel valve should be is not the correct part. If that thing is opening at idle, it will surely cause a high idle.

Edit: here is a thread of mine about the decel valve.
http://www.914world.com/bbs2/index.php?s=&...t&p=2956383

Leave the Aux Air Regulator/Valve alone for now as it should be open until the engine is warm.
But if what I’m seeing back there on your second picture is the AAV setup, its a hot mess and probably a big part of your problem.

[tshih914]

Whatever you have back there by the batter near where the decel valve should be is not the correct part. If that thing is opening at idle, it will surely cause a high idle.

Edit: here is a thread of mine about the decel valve.
http://www.914world.com/bbs2/index.php?s=&...t&p=2956383

Leave the Aux Air Regulator/Valve alone for now as it should be open until the engine is warm.
But if what I’m seeing back there on your second picture is the AAV setup, its a hot mess and probably a big part of your problem.

@van B
Lol the hot mess near the battery is indeed not stock. When I replaced the fuel lines I used the braided hoses to connect the steel lines in the tunnel to the non-stock metal fuel filter inline to the remnant plastic line feeding the engine fuel rails (temporary hook up since I intend to stick a 2L rebuilt engine when done in place of the 1.8L currently in place). That mess is not any vacuum hose causing/relating to my high idle issue.