Trouble shooting 74 L-Jet, Where do I start Options

[Levi]

My 74 1.8 L-Jet is giving me trouble, At start up, engine cold, it will idle rough (400-500 rpm) and seems to be loading up?, after 3 or 4 minutes the rough idle goes away and it will idle at 900 rpm's, but if I ease into the throttle it cuts out around 2800-3500 rpms, but I can rev it to red line. after driving it 2 or 3 miles it seems to clean out and runs great, however it will from time to time die when I have the clutch in while stopping.

Where should I start looking

[Dave_Darling]

You start just the same way you do if you have D-jet, or carbs.

Verify that the ignition system is in good working order. Make sure all the adjustments are correct, the parts are good and working nicely, and so on. Make sure that the "basic engine" is in good shape, that the valves are adjusted correctly and that the motor has decent compression. Make sure that all the wires and hoses are hooked up correctly, cleanly, solidly, and that none are brittle or cracking. Verify that the fuel pressure is correct for your type of system. (Haynes has the info for the L-jet, I forget the exact number.)

Then you check through all of the intake system for vacuum leaks. The rubber "boot" from the air flow meter to the throttle body likes to crack in between its accordion pleats, where it's hardest to see of course! The oil filler can leak air as well. So can the throttle body. So can other parts... Pretty much anything between the air flow meter and the cylinder head is a possible source of leaks!

Then you can move on to checking the actual FI parts. Haynes, surprisingly, has pretty good info on all of those! They're not quite all together, but they are in the Fuel System chapter and the tests are good as far as I can tell.

--DD