Haltech wiring ignition basic questions

[Zed Head]

Some ignition coils have their "dwell" controlled by the computer, like modern GM HEI coils which are almost zero ohms resistance.  Other coils use independent modules that have current-limiting circuitry that maximizes "charge" then holds it.

I did a Google and found an interesting article about coils and modules, below.  There's a bunch out there.  My basic point is that you should not even be considering keeping the ballast resistor for a modern ignition system.  It is a relic, although a cool (as in neato, but also a pun) one, for keeping current flow controlled through a coil used for points.  It only lasted three years after Nissan went electronic in 1974.  1978 did not use a ballast resistor.

Each system is different.  There should be details in the full installation manual about what you need for the coil; resistance, type of module, how to wire it, etc.

My other post was pointing out that the system is designed for independent coils per cylinder.  You only show one.  Maybe the Haltech 750 can run one coil for six cylinders but it's not clear.  That would be inthe manual also.

https://www.consulab.com/files/ignitionHandoutV20181.pdf

Edited July 1, 2021 by Zed Head

[Zed Head]

Here's some Haltech stuff.  Describes "Auto-Dwell", AKA current-limiting, and "ECU-Dwell", which is essentially using the module as high speed relay.  The module keeps the heat/current out of the ECU.

It's a fun topic, very energizing.

https://support.haltech.com/portal/en/kb/articles/ignition-modules

[Zed Head]

I don't want to overdo getting involved in your project.  But I found another thing that shows a parameter that looks like it's in the Haltech tuning software.  One of those things that could lead to problems if overlooked.  The dwell setting.  Depends on the module.

Also, the word "module" could mean what they call an igniter.  That would be the high speed relay that I mentioned above.  Requires ECU control.  That might be what your Denso coil has.  This is from the RB30 page.  All systems have similarities though.  Good luck. 

https://support.haltech.com/portal/en/kb/articles/rb30-engine

[Blitzed]

Thanks for the info.

The config attempting to set-up is not unusual but not the choice of most. The hall effect distributor purchased (new in the market) will allow the set-up to start with a single H.E.I coil, sequential fire distributor, easier to convert to EFI but for some not the most efficient (this is not a race car, drive). See distributor pic and hall effect signal provided by the unit. 

The nice option to this distributor is the ability to remove the distributor cap, install a distributor cover and run a distributor less coil pack or COP set-up in the future. 

First ECU install and EFI conversion so the leaning curve will be a single coil and sequential fire. Rotor phasing is complete (not test) dwell will be a programing function through the ECU. 

Apologize my initial post was about wiring in-line with stock harness as with new products /conversion you end up going down different paths.   

[Zed Head]

I think that you'll be just setting dwell in the software with the coil and power transistor (another name for ignitor, more correct) that you're planning to use.  There are probably recommended values to for the Denso PS coil.  Your setup will be like the system used on the 280ZX turbo engines.  Very common, used well up in to the 90's (my 95 Pathfinder had that system), probably still used today on some engines.

The dwell settings do the job, the most basic one, that the ballast resistor was designed to do.

[Blitzed]

Hello All,

Need some help with Haltech Elite 750 ECU install,  engine starts and runs well with all the new EFI ignition mods. 

Two problems have come up that may be related, not sure?

First - Has anyone experienced the Haltech ECU disconnecting from the PC after engine start or ignition?  Also installed a Haltech CAN gauge in the dash at 200 RPM the gauge freezes and reboots with disconnect of the ECU to PC.

So I must have electrical noise at start up? Running NGK R plugs (resistor style), Taylor sprio pro wires (made for ECU applications).

Could it be the new HEI coil (pic in this post upstream) with transistor igniter that's causing the noise?  Cranking dwell setting at 4 per manufacture spec?

Second - after the ECU disconnects from the PC engine will continue to run perfectly but the battery voltage is hovering around 15 volts. The coil is star grounded to the head not the battery. The only connection to the battery and coil is through the ECU coil wire and the ECU power wire to the battery.

How can test the to see if the alternator is the problem with the voltage reading or not?

Thank you for your help. 

[SteveJ]

I'm not sure exactly when you are experiencing this disconnect. I can tell you that when you release the key going from START to ON, there could be a momentary drop in voltage. It's nothing for a typical ignition (electronic or mechanical) since the inertia of the engine will keep things going during that gap. It might not hurt to reach out to Haltech about that. If it is a real problem, I could guide you on a possible solution.

[Blitzed]

Hi Steve,

Thanks, Haltech CS has been less than helpful. More for the experienced ECU installer and tuner. If they size you up as inexperienced, you're directed to the tech site and on-line support video's.

That's ok, my goal is to fully understand the system, wiring and subtle nuances with the L series engine. Better scenario when you find yourself on the side of the road :).

[Zed Head]

3 hours ago, Blitzed said:

the battery voltage is hovering around 15 volts.

Where are you getting this reading from?  A 73 alternator with external regulator can reach 15 volts.  It would be normal for certain temperatures.

[Blitzed]

Hi Zed Head,

From the ECU. The Haltech ECU provides a battery voltage non-run and running engine. Metered the battery with engine not running and voltage displayed from the ECU was very accurate, 12.38 volts not running (Optima Red top). When the engine is running the ECU is showing the voltage moving to 14.70 - 15.1 (red screen at 15+) warning for potential battery damage, ECU provide engine warning signals

California car, outside air temp is 85-90 degrees when starting.  

 

[Zed Head]

You might just clean up your voltage regulator and alternator connections to start off.  The regulator senses the alternator output and regulates accordingly.  If it's sensing incorrectly, maybe through a corroded connection, it might be allowing too much voltage. 

Find that page I copied from and you'll see that the VR is adjustable.  You could tune it down if the voltage stays high.  EE-23 shows the adjustment process.  Assuming that you still have the external regulator.

If you have already converted to an internal reg alternator, then move the end of the sense wire closer to the alternator output and/or clean those connections too.

 

[Blitzed]

Hi Zed,

Thanks for the info. Yes, new external regulator install 2019, before the ECU went in, engine was running fine and the same battery was installed, wasn't burning through batteries. 

Maybe over thinking the reading and 15, not an issue? The voltage does changes when running a will drop into the low 14 to high 13 but will also reach 15 number.

I'll check out the VR adjustment and take a look at the wiring at the alternator. 

Thank you