1.8L injector question |
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1.8L injector question |
Rob-O |
May 7 2023, 12:57 PM
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#1
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Senior Member Group: Members Posts: 1,252 Joined: 5-December 03 From: Mansfield, TX Member No.: 1,419 Region Association: Southwest Region |
Doing some spring work on the 914. Going to pull injectors and check spray pattern. I did some online research in case I need to replace one or more injectors. I don’t know about the 2.0L injectors but all I can seem to find for the 1.8L are ‘refurbished’ injectors. It made me think about 1.8L injectors in general, which are low impedance (the L-Jet uses a resistor pack of course). Is it even possible to use high impedance injectors, which I understand most vehicles use nowadays, and just remove the resistor pack? Is that a thing or is there more to it that would make newer (more plentiful) injectors work on older systems like L-Jet?
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technicalninja |
May 7 2023, 01:41 PM
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#2
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Senior Member Group: Members Posts: 1,290 Joined: 31-January 23 From: Granbury Texas Member No.: 27,135 Region Association: Southwest Region |
It's the "drivers" in the ECU that you have to be careful with.
These provide the ground path for the injector and high impedance injectors vs low impedance injectors need different drivers to work them. One way it doesn't fire the injector properly, the other way burns up the drivers in the ECU and doesn't fire the injector properly. I've not tried to swap high impedance to low or vis-versus. It can be done. Others have swapped before (often with issues that have to be worked out). I'd swap the whole system with modern stuff before I started trying different impedance injectors on a 50 year old ECU. A micro-squirt is many times better than the stock equipment and has massive tuning potential. You just need a laptop and a bit of training. After you get through the first application of a modern stand-alone the next ones are far easier to do. |
JeffBowlsby |
May 7 2023, 02:33 PM
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#3
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914 Wiring Harnesses Group: Members Posts: 8,524 Joined: 7-January 03 From: San Ramon CA Member No.: 104 Region Association: None |
I'd swap the whole system with modern stuff before I started trying different impedance injectors on a 50 year old ECU. A micro-squirt is many times better than the stock equipment and has massive tuning potential. You just need a laptop and a bit of training. After you get through the first application of a modern stand-alone the next ones are far easier to do. The OP only asked for an injector substitute and you recommend to convert to a custom FI and tuning leaves me speechless. Why not just recommend a whole new drivetrain (being sure to get the full injection)? The man just needs to fix what he has. 100% certain that a correct replacement injector is available. |
technicalninja |
May 7 2023, 04:26 PM
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#4
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Senior Member Group: Members Posts: 1,290 Joined: 31-January 23 From: Granbury Texas Member No.: 27,135 Region Association: Southwest Region |
You've taken my words out of context...
I'd replace the original injectors with the correct stuff FIRST as long as replacements were available. I'd try other injectors (of the correct impedance) before chucking the whole thing and replacing. They don't have to be Porsche, just Bosch. What I wouldn't do is try to modify the original ECU to accept different impeadance injectors before swapping everything over to modern. |
StarBear |
May 7 2023, 04:35 PM
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#5
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Senior Member Group: Members Posts: 1,905 Joined: 2-September 09 From: NJ Member No.: 10,753 Region Association: North East States |
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ClayPerrine |
May 7 2023, 04:41 PM
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#6
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Life's been good to me so far..... Group: Admin Posts: 15,498 Joined: 11-September 03 From: Hurst, TX. Member No.: 1,143 Region Association: NineFourteenerVille |
Doing some spring work on the 914. Going to pull injectors and check spray pattern. I did some online research in case I need to replace one or more injectors. I don’t know about the 2.0L injectors but all I can seem to find for the 1.8L are ‘refurbished’ injectors. It made me think about 1.8L injectors in general, which are low impedance (the L-Jet uses a resistor pack of course). Is it even possible to use high impedance injectors, which I understand most vehicles use nowadays, and just remove the resistor pack? Is that a thing or is there more to it that would make newer (more plentiful) injectors work on older systems like L-Jet? Rob, The 912E/Nissan 280ZX injectors are plentiful and a bolt on replacement for the L-Jet injectors. Just go to FLAPS and order a set for the Nissan. Clay |
Van B |
May 7 2023, 06:47 PM
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#7
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Senior Member Group: Members Posts: 1,612 Joined: 20-October 21 From: Maryland Member No.: 26,011 Region Association: None |
NOS is still out there under the bosch part number, but after my experience of buying 7 just to get four that worked makes me think Clay has the right idea. I know the nissan flows just slightly more, but not enough to require a tune of the AFM
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Van B |
May 7 2023, 06:49 PM
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#8
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Senior Member Group: Members Posts: 1,612 Joined: 20-October 21 From: Maryland Member No.: 26,011 Region Association: None |
If you have a resistor pack issue, that pack superseded to a number ending in 014. It was used on volvos for a while so there are plenty of good used ones still out there
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brubou |
May 7 2023, 07:09 PM
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#9
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Bruce Bouchard Group: Members Posts: 92 Joined: 29-February 16 From: West Bradford, PA Member No.: 19,716 Region Association: MidAtlantic Region |
If you’re pulling the injectors just send them to Mr Injector, they come back looking and spraying like new and it’s very reasonably priced, cheap even
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Geezer914 |
May 7 2023, 07:11 PM
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#10
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Geezer914 Group: Members Posts: 1,433 Joined: 18-March 09 From: Salem, NJ Member No.: 10,179 Region Association: North East States |
Rock auto has injectors. Standard Motor Parts.
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Rob-O |
May 7 2023, 09:41 PM
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#11
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Senior Member Group: Members Posts: 1,252 Joined: 5-December 03 From: Mansfield, TX Member No.: 1,419 Region Association: Southwest Region |
Thanks for the replies. I understand where @technicalninja is coming from. I was just thinking out loud on feasibility. It seems every new day another part is unavailable. We’re pretty blessed with the parts availability we have but it still takes time for a new supplier to come online once a part is no longer made by the manufacturer.
I’ve thought about Microsquirt. I really, really want to keep L-Jet but I’ve never been satisfied with how my car runs with it. I installed L-Jet (had the crappy single Holley carb setup). Sourced all the parts, checked all the parts for functionality before installation. Checked the wiring harness to ensure good connections, had the injectors cleaned, bought new parts where needed, had the throttle body rebuilt, new fuel pump, known hood AFM, have fought and fought but my fuel injection just isn’t reliable. I know they can be but I’m lost. Current issue is that it starts right up and idles at 800-900rpms. After a few minutes the idle starts hunting, dropping before it catches itself and goes back to 800-900. It does this for about five to seven minutes of driving. Once the car get up to operating temp it’s back to a smooth idle. At any time after I start it it can and will frequently just shut down when at idle. It starts up every time afterwards with no issue but it doesn’t make driving a joyful experience. One other thing I notice is that when there is current draw (i.e. lights on) the hunting idle and abrupt shut downs happen more frequently. |
Rob-O |
May 7 2023, 09:56 PM
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#12
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Senior Member Group: Members Posts: 1,252 Joined: 5-December 03 From: Mansfield, TX Member No.: 1,419 Region Association: Southwest Region |
Doing some spring work on the 914. Going to pull injectors and check spray pattern. I did some online research in case I need to replace one or more injectors. I don’t know about the 2.0L injectors but all I can seem to find for the 1.8L are ‘refurbished’ injectors. It made me think about 1.8L injectors in general, which are low impedance (the L-Jet uses a resistor pack of course). Is it even possible to use high impedance injectors, which I understand most vehicles use nowadays, and just remove the resistor pack? Is that a thing or is there more to it that would make newer (more plentiful) injectors work on older systems like L-Jet? Rob, The 912E/Nissan 280ZX injectors are plentiful and a bolt on replacement for the L-Jet injectors. Just go to FLAPS and order a set for the Nissan. Clay What year 280zx, Clay? I had all of the injectors cleaned when I installed L-Jet (you were there for that!) but at some point Ed M. replaced one of my injectors. I notice that it has a green connector…as opposed to the other three, which have brown connectors. When I had the injectors cleaned they also cleaned the CS injector. Car has a 123 dizzy (Bluetooth) and a new Bosch blue coil. That has helped how smooth it runs when it’s at speed but hasn’t helped eliminate the idle and shut down issues. No leaks on the intake side of things (did a smoke test). The issue feels electrical in nature. The temp sensor in the head is somewhat new (from 914Rubber). Installed a short time after L-Jet was reinstalled. I’ve cleaned and checked just about every connector I can think of in the engine bay. Ignition switch was replaced a few years ago. Didn’t help. Cleaned connectors on relay board but didn’t pull it to look underneath. AFM was from you. Haven’t touched the insides. Cleaned and verified AAR/AAV is working. |
ClayPerrine |
May 8 2023, 05:46 AM
Post
#13
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Life's been good to me so far..... Group: Admin Posts: 15,498 Joined: 11-September 03 From: Hurst, TX. Member No.: 1,143 Region Association: NineFourteenerVille |
Doing some spring work on the 914. Going to pull injectors and check spray pattern. I did some online research in case I need to replace one or more injectors. I don’t know about the 2.0L injectors but all I can seem to find for the 1.8L are ‘refurbished’ injectors. It made me think about 1.8L injectors in general, which are low impedance (the L-Jet uses a resistor pack of course). Is it even possible to use high impedance injectors, which I understand most vehicles use nowadays, and just remove the resistor pack? Is that a thing or is there more to it that would make newer (more plentiful) injectors work on older systems like L-Jet? Rob, The 912E/Nissan 280ZX injectors are plentiful and a bolt on replacement for the L-Jet injectors. Just go to FLAPS and order a set for the Nissan. Clay What year 280zx, Clay? I had all of the injectors cleaned when I installed L-Jet (you were there for that!) but at some point Ed M. replaced one of my injectors. I notice that it has a green connector…as opposed to the other three, which have brown connectors. When I had the injectors cleaned they also cleaned the CS injector. Car has a 123 dizzy (Bluetooth) and a new Bosch blue coil. That has helped how smooth it runs when it’s at speed but hasn’t helped eliminate the idle and shut down issues. No leaks on the intake side of things (did a smoke test). The issue feels electrical in nature. The temp sensor in the head is somewhat new (from 914Rubber). Installed a short time after L-Jet was reinstalled. I’ve cleaned and checked just about every connector I can think of in the engine bay. Ignition switch was replaced a few years ago. Didn’t help. Cleaned connectors on relay board but didn’t pull it to look underneath. AFM was from you. Haven’t touched the insides. Cleaned and verified AAR/AAV is working. 1980 280ZX injectors "Standard Fuel Injector | FJ707" Direct drop in replacement. |
L-Jet914 |
May 10 2023, 12:47 AM
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#14
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Member Group: Members Posts: 248 Joined: 24-October 12 From: Davis, CA Member No.: 15,080 Region Association: Northern California |
RockAuto under 74 914 1.8L new not reman part number SMP FJ6.
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