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Posted by: rbzymek May 23 2019, 08:57 PM

So the 1975 1.8 is getting L-Jet fuel injection. I am in the testing phase and need to know if the power supply and fuel pump (round) relays need to be populated on the relay board. I was under the impression that the dual relay provided power to the fuel pump. I will trace out the circuits but I thought I would ask the question any way. Thanks in advance.
Ray

Posted by: porschetub May 24 2019, 12:46 AM

Go to the 914 info link @ the top of the home page,shows what your relay board has.
Not @ all sure with L-Jet on the 1.8 but seem to remember from info on here and others that that resistor block is for the injectors ??
Your pump gets the signal from "key on" and uses the FI power and fuel pump relays to prime the system before you start cranking.
Make sure your AFM is up to spec ,these can be DIY repaired with parts from vendors on here,914rubber on here is a good example.
Don't trust my info as its off the top of my "old brain" .

Posted by: rbzymek May 24 2019, 02:49 PM

Thanks for the suggestions.

Posted by: ClayPerrine May 24 2019, 08:45 PM

While what you just said is true for D-Jet, it is not for L-Jet. The L-Jet system will run even if there are no relays in the relay board. There is a "double relay" that mounts to the battery support. It is used to provide fuel when the starter is engaged, and also when the air flow meter is opened.

There is a special engine harness for the L-Jet cars. It has an extra connector with a power loop in it, and it has a yellow wire with a female spade connector on the same end as the 12 pin connector. The yellow wire connects to the either of the rear spade connectors on the 4 pin connector on the left rear of the relay board.

Make sure you have the correct engine harness before you try to hook anything up. Otherwise you will never get it working.

You can find a lot of reference material http://http://bowlsby.net/914/WiringHarnesses/