The PO had a single carb on when I bought my 74’ 1.8 914 and said he had uneven idle problems with the L-jet injection so he preceded to remove all components and box everything up. So now I’m feeling I want to reinstall the injection and put it back to stock. I have some mechanical ability and patience, though I was never able to get that gas smelling carb to run right. Was looking for someone I could pay for a few hours to kinda orientate me on the location of the box of injection parts I have and give me thoughts on what parts I might be missing and how difficult and expensive it will be to put everything back. I’m in Puyallup WA south hill area, Thanks In advance

Shane there is a character & longtime member in your backyard who goes by the moniker @Rhodyguy I believe he's retired but still has a 914 (I think) so he may be a good resource (at a minimum for traffic advice) otherwise call me Ill help however I can.

Great! thank you

I can help. If you post pictures of what you have, I can help you figure out what you are missing.

Clay

HERE

Great thanks I’ll post after work today

Thanks

Click to view attachmentClick to view attachment

Click to view attachment and a decent fuel injection harness

Might be something as simple as cracks in the back of the snorkel. L-jet can barely tolerate any vacuum leaks so that’s likely a big part of it. Have the injectors checked out and rebuilt if necessary (probably, because they’ve been dry for so long) then go through all the seals and replace them. Make sure the vane operates freely in the AFM.

It’s not a complicated system, and this site is a great resource.

Good luck

Thanks, how complete is my collection at first glance? Trying to figure out what I might be starting and will need right from the beginning. Thanks

Looks like you have all the major parts of Ljet.

https://www.pelicanparts.com/914/technical_...4_18FI_diag.htm

Click to view attachment

At first glance looks to be pretty complete. I dont see a FI wiring loom, thermo-time sensor or specific Oil fill neck

i encourage you to do it.

its a primal system. first time install in the world in a car of L jet (but maybe simultaneous with vw 412 but all in the family).

beat SAAB and those eager smug do gooder swedes.

bring it back.

inspect that part # on the flow meter connected to the air cleaner.
Bosch etc 001. says it all. crack a beer after you do it and let me know.
i'll rip the top of a can down here.

Another reply from down under

Go with the L Jet. When correct it is so smooth and starts off the key even if not run for a month or two.

You look as though you have all the bits. I can’t make out the dual relay but I suspect it is still there.

Check the action of the throttle body. They have a tendency to stick in the closed position but can be re worked by one of our vendor members - the thread is titled “Throttle Body re machining”. His work is top shelf

Good luck

Does look very complete, the dual relay is present. Sometimes the part most damaged during removal is the harness, old wiring don’t like getting wanked around. So maybe a new harness from @jeffbolsby is in order, not cheap but will no doubt ensure many years of trouble free performance.

It really isn’t a complicated system. Just be methodical with the replacing. David’s throttle body suggestion is also very good. Make sure your CHT sensor is good. Move your fuel pump to the front trunk.

Have fun!

There is a thread on here to convert an L-Jet system to use a larger vanagon throttle body. I did it, and it is worth the time it takes. The throttle body on a 914 L-Jet system is very small, and chokes down the engine. Adding the larger throttle body woke up the engine on Betty's car.

Vanagon Throttle Body for L-Jet

Clay

You will need both the L-Jet FI harness and L-Jet Ignition harness. I have both of them available as new and as refurbished originals.

The new harnesses would be the hot ticket. For the injectors, Witch Hunter services them and are located in Duval.

Just buy 4 new injectors for a 1980 Datsun 280ZX. They are plug and play, with a slightly higher flow rate.

What do those cost each? If the stock core injectors are serviceable, it's $24 a pop +shp. Those parts look really clean. Not left about in some bucket or box. Is increased flow an issue on the 1.8s?

There is so much knowledge on here, these guys will get you walked through. I also have a 74 1.8 I replaced leaking seals, etc. I attached an overhead of the FI. If you need any pictures of where things connect, plug-in, etc. feel free to reach out. Click to view attachment

The Standard motor products injectors for the 280ZX are about $50.00 a pop, brand new.

The Beck Arnely 158-0099 fuel injector is about $60.00 a pop, brand new.

To me, fixing L-jet injectors is false economy, considering how cheap new ones are.

Have you looked at the potentiometer board under the black cap on the Air Meter?
A nice close up photo could answer questions there.

now thats a red hot tip.
wish i had been here and asked that question a year ago.

supply of orig injectors is drying up.

I’ll definitely take you up on that! I almost don’t know where to begin (but seriously I don’t know where to begin) hate installing things in the wrong order and shooting my self in the foot. Was going to start this endeavor this weekend. I’ve never seen a FI system on a 914 so it’s a little overwhelming and the Haynes manual is limited on pictures. I’ll shoot a couple pictures of brackets and stuff and ask locations. To bad a single carb doesn’t do the trick so simple, this is my starting point before pic minus some stuff soon the engine compartment will be a jumble compared Click to view attachment

Let me know what pictures you need. The engine with L-Jet from Betty's car is sitting on a stand in my garage. So pictures will be easy to get right now.

Do you have the bracket and Aux air regulator? I didn't see it in your pictures.

Clay

I thought I had the regulator and I have a black bracket it’s in the photo with my plenum and Gray intake runners

AAR in the middle of your picture.

Click to view attachment

I’m thinking this part? in the picture had a cover and I was told I need a thermo-time sensor. So I’ll be looking for these items as well as anything else I don’t have.Click to view attachment

That is not part of any L-Jet system I have ever seen.

Clay

Okay, Kind of a mystery part I’ll take a better picture of it and post it. Was in the box of FI parts the PO gave me.

think what you call thermo time sensor would be thermo switch.

connected to the cold start injector.
obscure location under the intake plenum.
fortunately i have never had to get at it!

it switches the cold start injector on for about 10 seconds and then switches it off.

someone who has had the engine/EFI apart might have a photo as its easier to see with engine out of car.

there is a photo in the factory manual and reference to
"unscrew thermoswitch with an appropriate tool".
but its cryptic.

Here is a L-jet Thermo-switch (sans brkt)
Click to view attachment

Sorry...
the first car with L-Jetronic was the Opel Manta A GT/E from march 1974 on. Has been sold in the USA, too.

Regards
Norbert

Never knew about the Manta Norbert.
not a bad looking car, never got those in aus.

my 914 1.8 L jet is a jan 74 build.
model years commence production in the second half of the previous year.
us market vw 412s also had the 1.8 with L jet along with 914s.
that puts both of them in august 73 start.

i should have said the 914 shares that first use with the 412.

bosch 001 # on the air flow sensor might be on the opel too.
don't know. the cars that have the 001# are first to use it and its the first version of the system.

far as i know vw/porsche reverted to twin carbs on home market 74 1.8 models. that would indeed make the manta the first car sold in germany if it had L-jet on the domestic models.

i think its the same for aus. we got twin carb versions of the 2.0 type 4 engine on the kombis when they came here. no L-jet. L jet only in the USA.

*
EDIT - here is the list i have now with manta included thanks to your prompt.
tracked it down. its all on the air flow meter - the critical part and tells you which order bosch assigned the #s to the system chronologically. cars themselves might be released earlier than the system chronology. are you sure the manta isn't released earlier than march 74 in germany. if it is, it is the first in the world.

0 280 200 001 - 74 porsche 914 (also maybe vw 412) USA
0 280 200 002 - supposed to exist but never found info on it.
0 280 200 003 - 74 opel manta GT/E
0 280 200 006 - 75 VW beetle USA
0 280 200 012 - 75 VW kombi USA

it goes on through a few more kombi USA models.
some other cars start sharing the systems.

as far as i can tell there were no 004, 005 or 007-011 numbers assigned.
system projects abandoned?

i think the SAAB might have been first to use the K - jet which was offered at the same time as L jet. its a mechanical system not electronic. but uses an air flow meter.
bosch were backing two horses. porsche took up the K jet on the 911s but i think SAAB beat them.

i dug all this up when i was on a rampage to find injectors etc before the world supply of obscure parts completely dried up.

i feel for the manta guys - they would be in the same boat as 914 L jet owners.

Click to view attachment Click to view attachmentClick to view attachment Click to view attachmentClick to view attachment
Hopefully this gives you some idea of the steps to assemble. Basically I didn’t install the intake pipes until towards the very end.Click to view attachment

nice images of a beautiful build mr. m.

can see the thermo time sensor mr. s is missing hiding out under the plenum left of cold start injector in first photo.

Thank you so much that’s exactly what I needed to try and get started. Does the underside of the plenum bolt down? And where does this bracket go? Hoping that once I get some of the big pieces of the puzzle together it will get much easier Click to view attachment Click to view attachment

I definitely have to powder coat my plenum silver instead of the black I have on it now though

that is your air cleaner bracket. mounts off the body if i remember right.

Click to view attachment Click to view attachment

Correct there should already be a set of threaded spots on the L. long in the eng . bay to mount it.

You should be able to set your parts in same areas as shown in the pictures and see where either you bolt something to or have to utilize the case half bolts to bolts things on. Just remember to torque everything to proper specs when putting back on car.

Yes - you are right!
I'm getting old - or - better said - I am old!
I always reflect to the cars I worked on in those days...
and German car tech information tells the same as I did: https://kfz-tech.de/Biblio/Benzin-Einspritz.../L-Jetronic.htm

I discussed the theme with Volker Huck three years ago and forgot it: https://jetronic.org/de/forum/hinweise-und-...etronic-familie

Best Regards
Norbert

no worries norbert.
my grandmother was german.
its coursing through my veins.

the main thing is the germans did it.

opel/vw who cares.
its german mate and they knew how to do it.
we are talking about mere months here, weeks even.
bosch were on the game and the germans did it first.

and ps.
down here we got the crap english vaxhaul british gm stuff, untiil holden just decided to go american on it and stick giant motors in those crap uk gm things.
i wish they had have sold opels down here. the manta is a cool looking car.
anything german, even the gm stuff is ok by me.

anyway - back to main topic
helping this guy get his "technologically advanced mid/late 20th C fuel injection system" back on the car instead of running t rex carbs. not that t rex is short of taking notice of. but the future according to 1974 is worth taking notice of too.

Received my injectors back, the hoses are pretty straight and hard to bend will that be to much stress on the injectors? I have most of the gaskets and stuff needed to install now. The plenum lines up with the studs on the case but I don’t know if the front stud has a nut on it then another one for the plenum? Also I’m missing I think a harness strap and something else that mounts directly under the plenum? Would appreciate advice thank you in advance for any help [attachmentid=780891Click to view attachment

I'm pretty sure it was engine case, plenum then a nut. If the rubber lines are hard and brittle, it would be a good time to replace them. Go ahead and replace them with the slight radius style, it came that way from the factory. Lastly, make sure you clean these terminals that I circled in the picture. A bad connection here will cause a bad day of troubleshooting in the future.
Click to view attachment

A slight highjack with this thread and perhaps Clay or others might chime in. I'm planning on going with the vanagon throttle body conversion. I think I found a cheap enough 50mm throttle body and have done research on good double sealed INA needle bearings to rebuild this potential 50 mm throttle body. However, I came across this GoWesty throttle body. Will this bolt up and play nice with our 1.8L's I do understand I'll have to fabricate something for the throttle body switch.
Click to view attachment

Thanks, good luck with your project

Hey Shane, curious if you sent all 5 injectors to Mr. Injector for cleaning? The cold start valve is often overlooked.

Yeah I’m an idiot!!! I knew it was an injector but never occurred to me, I could still send it in though. I’d ask first to make sure he cleans them. Thanks for the info