I'm looking for an ECU to go on a 1975 1.8 engine. However when I look for a computer theres about 100 different numbers and letters with it and I have no idea how to check with computer will work with my engine. I have two possible computers to use and they both end with a different letter. I have no idea how to tell which one needs to go on my car. The next question would then be what jets do I need. I have two different type of jets. An I jet and an L jet.

280 000 104 = CU65X = 1974 1.8L
280 000 111 = CU66X = 1975 1.8L

and if you are uncertain that the unit is bad, you can always send it here to service and we will test for you

Not sure what you need. I've never heard of an I Jet, but L Jet is short for the Bosch L Jetronic Fuel Injection system which your 75 1.8 should be equipped with. L=German for luft (air). The ECU (engine control unit) is a part of this system.

The 1970s ECUs are really robust. They don't often fail because they were built with big, huge transistors, resistors and caps, no Integrated Circuits. They are really hard to kill.

If you can give us some of the symptoms you are experiencing, we may be able to help you get it running.


Clay

I'm adding the system back on. I previously had the carbs in the car but since I have all the proper parts for the ecu and i have computers i might as well use the computer.

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[quote name='Ecoleft' post='2751726' date='Oct 2 2019, 01:55 PM']
[quote name='JeffBowlsby' post='2751122' date='Sep 29 2019, 04:37 PM']
280 000 104 = CU65X = 1974 1.8L
280 000 111 = CU66X = 1975 1.8L
[/quote]
The next set of numbers (the file is too big and wont let me post) is 022-906-021 B
And under the Bosch logo is 0280-000-015

your picture shows a ECU from the D-jetronic your car has original a L-jetronic .

The 037 ECU is correct for either a 1973 1.7L or 2.0L engine. Engine swap from the original 1.8L?

The ECU you show looks like it has been wet for a long time.

No these are spares we have for the car. So should I invest in a new ECU?

[quote name='Ecoleft' date='Oct 2 2019, 01:56 PM' post='2751727']
[quote name='Ecoleft' post='2751726' date='Oct 2 2019, 01:55 PM']
[quote name='JeffBowlsby' post='2751122' date='Sep 29 2019, 04:37 PM']
280 000 104 = CU65X = 1974 1.8L
280 000 111 = CU66X = 1975 1.8L
[/quote]
The next set of numbers (the file is too big and wont let me post) is 022-906-021 B
And under the Bosch logo is 0280-000-015
[/quote]

Do you know if you have an L-Jet system or a D-Jet system? If you don't know, just post some pictures of the rest of the EFI system and we can tell from them.

I actually have both systems. Just dont know which to use. I'm rebuilding the car after some serious fire damage

Please be more forthcoming with all details of exactly what you have and what exactly you are trying to accomplish. We are not going to keep guessing and draw it out of you little by little.

Sorry. I'm still new to this. I am rebuilding my Porsche 914 again after it caught fire in the engine bay. I have all the parts I could possibly need but I dont know which jets I should use. I have both d and L jets and I have the engine computers. I dont want to use the wrong computer for my car. So I am asking as to what I should use for my car. Since I have both jets and multiple ecu's for the car. Does it even matter?

Yes. You can not hook up an L jet ecu to a D jet harness. Completely different systems. Many other differences. Do you know what parts are D jet and which are L jet? If not post pictures of what part you have.

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