Introducing myself and a request!

[SouthCarolina83]

Hello all I’m Scott in Summerville, SC! I have an 82 280ZX N/A and I’m desperately trying to get an 83 280ZX running I paid 100.00 for.

I apologize in advance if I’ve posted this in wrong place... I’m having an issue getting an EFI pulse from ECU on the 83. I’ve got 12VDC on all six injectors plugs on one pin with key off and I’ve got a very dim yellow pulse on each plug when I turn it over with a NOID light installed. How bright should the light be? It stayed the same yellowish color as I moved it from plug. I currently have the fuel rail pulled up with injectors still connected to rail. All electrical checks have been made with all six injector plus off all injectors. I’ve also tested each injector with test leads off the battery and have mostly good flow from injectors.

im trying to ensure my fuel issues are fixed prior to removing the intake and exhaust manifold to replace gasket and drill out broken end studs. I’d like to replace fuel rail, any recommendations on who and what to order? Also if my exhaust manifold is warped (I bet it is) what are options and what/where to get?

Thanks in advance,

Scott in South Carolina 

[dutchzcarguy]

6 hours ago, SouthCarolina83 said:

I’ve also tested each injector with test leads off the battery

Hi Scott welcome here..

I sure hope you used some resistors with that test otherwise you will blow those injectors strait to heaven!   A direct 12v from the battery is most times fatal..

a good way to test can be a 9v battery pack the very small ones you find in a remote or so..  these can deliver enough energy to test the injector, but not enough to burn them..

I advice you to FIRST read a service manual of the s130, you can find these on this site..

Then.. why should your exhaust manifold be defective.. first take it of and check for deformation with a strait edge.. there are ways to make it strait again..

good luck.

[SouthCarolina83]

I have the FSM on PDFs and have been using that for troubleshooting. I also wasn’t keeping 12 volts on the injectors more than a second at a time. I pulsed them. My plan is to replace them all when I replace the trombone original fuel rail with an updated single one. I’m looking for recommendations for that part from you guys. As far as the exhaust manifold goes I’m thinking ahead because my 82’s manifold was so warped I couldn’t use the thrust washers (combo bolts) to seal the intake and exhaust after milling it. My BiGGEST question from you guys right now is how bright should a NOID  light  light up when just cranking over the motor (not starting) at each injector connector? My light is just a dull yellow color for each flash/pulse.

scott

[Reptoid Overlords]

Not entirely sure about the NOID light brightness.

As far as new fuel rails go, I have been using this one from Z car depot that comes with an adjustable FPR. Of course you can get a separate FPR altogether and piece it all together yourself. I am using aftermarket EFI (FAST EFI) and decided to use the 14mm injectors that are found in post 2000 Ford and GM vehicles.  It is my understanding that the stock EFI won't run them properly.  So you'd have to select the option for stock fuel injectors for stock EFI. 

https://zcardepot.com/collections/fuel-injection/products/fuel-injection-rail-kit-with-regulator-efi-280z-280zx#

 

[Racer X]

13 hours ago, SouthCarolina83 said:

 Also if my exhaust manifold is warped (I bet it is) what are options and what/where to get?

Hi Scott, welcome to the clubhouse, and the Datsun world.

If you have checked the manifold with a straight edge and it is out of spec, find a competent machinist who can true it up for you.

[SouthCarolina83]

Thanks to both posts! I just got reminded nicely by my wife that we have a fully functional 82 280ZX on the driveway we can hook the noid light to to ck brightness. You mentioned an after market EFI, how does it hook to the ECU? Also looks like a header on yours? Where did you get it?

scott

[zeeboost]

The fact that the noid light is pulsing is a good sign on its own. Levels of brightness can vary depending on several factors, but I wouldn’t focus too much on that. Remember it will also be dimmer while cranking as you essentially drop from 12 to 9-10v. I’m assuming from your original post that you can physically see the injectors are not spraying fuel while cranking, but they are spraying when you jump each one over with the battery, correct? If so, I would verify the integrity of all grounds running to the ecu. It wouldn’t be a bad idea to verify harness integrity as well. Remember, even just one good strand of copper in a wire will pass the resistance test, but may not be able to carry a load. But we can worry about that later.
 

First, rule out if it’s lack of power or lack of ground preventing the injectors from firing. You can try this by turning the key to on to supply the power and then manually temporarily grounding the injector on the appropriate pin. If you’re concerned about damaging the ecu while doing this test (hasn’t happened to me yet), you can de-pin the ecu connector of the wires that drive (ground) the injectors, then plug it back in. If they work when you manually ground them, I would be leaning towards a grounding issue. If they don’t, then I would be trying to figure out why there’s power being lost. Maybe just a weak battery? Dirty contacts in a relay that supplies power to the injectors? Weak fusible link? Have you tried cranking it while the battery is on a charger? 
 

Lastly, is the fuel good? Does the engine run on supplemental fuel (like starting fluid)?

The good news is these are about the most simplistic efi setup to troubleshoot and work on, so just take your time going through the fsm and enjoy. 
 

[SouthCarolina83]

Starts and runs 5 seconds on starter fluid. Battery is strong and on charger. My issue is I want to verify the efi issue before tearing the intake and exhaust off and drilling out broken (factory defective) studs at outside number 1 and outside number 6 exhaust ports on the head. My plan is to junk the trombone fuel rail and all injectors and start fresh. If I swap to a single rail and the Ford/GM injectors do they use a new harness? What’s involved mechanically to do it? Also will the stock exhaust flow enough with different injectors?

Thanks in advance,

Scott

[Zed Head]

Seems like your injectors are opening as they should.  They need 36 psi behind them though in order to squirt.  I don't see any fuel pressure information.

[Reptoid Overlords]

1 hour ago, SouthCarolina83 said:

 My issue is I want to verify the efi issue before tearing the intake and exhaust off 

If I swap to a single rail and the Ford/GM injectors do they use a new harness? What’s involved mechanically to do it? Also will the stock exhaust flow enough with different injectors?

 

 

It seems like there's three parts to this thread.

1. EFI troubleshooting

2. Change/upgrade certain fuel components.

3. R&R exhaust manifold for straightness/ fix mounting studs/and intake/exhaust manifold gasket.

I don't want to complicate things by adding aftermarket EFI possibilities when your stock system can most likely be put  into a good functioning condition.  I would urge you to follow the troubleshooting steps put forth by others.  Stock EFI works perfectly fine for a stock engine(stock cam/internals etc.)

That being said, an aftermarket system will essentially replace the existing stock ECM/ECU.  Any aftermarket EFI will require the use of a new harness(I'm about 95% sure)

Again, it is my understanding that the stock ECU will not run the 14mm O-ring type Ford/GM injectors.  But I've never tried it. 

As far as I know, the stock exhaust manifold will flow just fine with different injectors.

You can install headers and run stock EFI, or aftermarket with no modifications/tuning required.  I have these headers:

https://www.thezstore.com/page/TZS/PROD/classic19c/15-6004

Edited April 4, 2021 by Reptoid Overlords

[SouthCarolina83]

Well the noid light blinks the same in my 82 so obviously the issue in 83 might be fine. I guess I’ll start the intake/exhaust manifold removal tomorrow and call to order a new fuel rail and injectors.

[Zed Head]

16 hours ago, SouthCarolina83 said:

have mostly good flow from injectors.

Are you sure the fuel is good?  Your cold start valve should also be supplying fuel for starting.

1 hour ago, SouthCarolina83 said:

My plan is to junk the trombone fuel rail and all injectors and start fresh.

This won't solve any problems.  Good luck.