Hello all and happy holidays,

I am battling a problem with my L jet 82' and I need a little assistance. About six months ago I was running down the road and my engine died. It made no unusual sounds but died as if it just lost spark or fuel. In troubleshooting I replaced the ignition switch, injector relay, and fuel pump relay. Throughout this process the car would start and run fine but occasionally the engine would die and not restart for hours (cool down time?) Anyway, I replaced the green wire and all the intermittent engine cutout problems went away and I enjoyed about a thousand miles of troublefree driving. That is until a few days ago when the engine quit running on the way home from a state vehicle inspection. No unusual mechanical noises, just seem to die like before. Upon starting attemps the engine will catch and run for a few seconds at a very rough and low RPM then die. During these starting attemps I have tried to slightly apply a little throttle but that actually kills the engine immediatley. I switched out the injector relay but still not difference. The engine is getting fuel (plenty of flow at the fuel rail) and it has to be getting spark or it wouldn't run for those few seconds.

Any ideas where I should focus my troubleshooting efforts.

 

I am not familiar with the '82 but it sounds like you may have fuel in the rails but not in the cylinders. Pull a plug and look at the condition - wet with fuel would indicate a spark problem while dry would indicate a fuel delivery problem.

Assuming it is a fuel delivery problem check your injectors with a noid light or check all of the injector wiring for a possible short. I believe if there is a problem with one injector wiring connection none will fire.

 

OK, I suspect this is the problem, because this happened to me, but not quite as “cleanly” as you describe.

On the throttle body, below the “spider’s body” of the intake, there are two large vac. ports (passenger side) on the US 4.5L cars. They are usually used as vac sources for various things in non-US cars, but for us, they are simply plugged.

If one of these plugs falls out, the air/fuel mixture is totally off because the intake sucks in air that was not measured by the airflow meter, and the mixture gets very lean. The car will start for a second or two then die as the mixture is adjusted by the L-jet, based on the airflow sensor’s signal.

It’s possible but not easy to replace these plugs w/o taking off the intake, and I managed to do it even with my big hands. Finding the exact part to plug the hole seemed like overkill to me, so I “Farm-engineered” a rubber stopper, a short hose and a couple hose clamps to do the trick. If you feel official, here's a picture. The part is 24A. - Ruf

 

"If" the plug method is what you need to do- I pluged mine with a few heater hose block off's from local parts store - just a couple of bucks.

 

I had this happen to me also, it would start and run for a few seconds off the fuel from the cold start valve. After troubleshooting every ground, sensor and connector, it turned out to be the L-jet controller.
Someone suggested a noid light earlier, I wished I'd looked at that earlier in the troubleshooting...
It's $12 at HarborFreight for a full set of them.

"Farm Engineered"... that's funny stuff right there!