Haltech wiring ignition basic questions

[Blitzed]

Hi All,

Thanks for the info and pic on venting. 

[Captain Obvious]

11 hours ago, Blitzed said:

Is the stock config a open or close system? Would the stock hose and PCV valve to the manifold be considered a close system? as the PCV valve will open and close only under pressure changes.

If pressure escapes to the valve cover and the vent hose is connected to the back of the air filter housing, wouldn't this be considered an open system?

The original system is considered a closed system. By "closed" they mean that there are no running conditions under which the crankcase vapors are released out into the atmosphere.

PCV theory says that pressure escaping out of the valve cover nipple would only occur under high blow-by conditions. And in a healthy engine, that would only occur at high throttle high load conditions. If that's the case, your carbs are sucking a lot of air and anything that gets pushed out into the air cleaner box turns around and gets sucked into the carbs and is burned in the engine.

PCV theory also says that under low blow-by conditions the crankcase vapors are pulled into the intake manifold through the PCV valve.

The vapors never escape out into the atmosphere, and hence is a "closed system".

If you're running one of those little air filtery thingies on your valve cover nipple, then its not a closed system anymore. If you're running catch cans with little filters on them, it's not a closed system anymore.

[crayZlair]

Yeah, I should have added the disclaimer "For Off Road Use Only" !

[crayZlair]

27 minutes ago, Captain Obvious said:

If you're running one of those little air filtery thingies on your valve cover nipple, then its not a closed system anymore. If you're running catch cans with little filters on them, it's not a closed system anymore.

See previous post ^^^^^^^

[Blitzed]

Thanks for the responses.  

[Blitzed]

Hi All,

Close to turning the key on the Haltech ECU / EFI conversion. I decided to move the inlet fuel filter to the engine bay. See pic. Felt it was easier to service. 

Duffy- I'm running a return fuel set-up with the fuel pressure regulator on the return line, are you running a fuel filter on the return side? 

Thank you,  

[Blitzed]

Hi All,

240z Wiring harness , L28

The EFI set-up is complete. Worked with Haltech remotely engine is running but chasing down a vacuum leak. Also having a weird issue with the electronic distributor connection to the ECU. Losing the signal grounds randomly. 

Question. Need to add a grounding strap from the chassis to engine block. Why, attempting to move my star ground (all required ECU ground connections) to another point (currently chassis).  Where is the best connection point? The engine bay harness is a stock 73 240Z. Is the chassis ground under the battery box off the harness a good point for a chassis to engine block strap? The FSM manual will not help with this issue, adding ground connections.

Also running a single coil with igniter (no problems), all the stock 240z distributor coil, distributor, resistor wires have been terminated and secured. Harness is still intact on left front fender. Is there a usable ground wire in from the old harness for a chassis ground?  

Thanks,  

[cgsheen1]

Ordinarily if you're adding a ground strap it would be from the block to the firewall - normally from the starter or transmission bolt to a bolt location nearby on the firewall. I've never found that necessary on a Z car but it certainly can't hurt especially if you're unsure if the stock wiring is "still stock".

The intake manifold is generally where you ground all your EFI equipment. EFI grounding can be very specific, and you need to avoid ground loops. Most standalones require all signal grounds to a single point (usually on the ECU itself OR prescribed in the documentation to a specific location) and the other ECU grounds all tied to one spot - either directly to the BAT or block (intake manifold IS same as block (and normally the main battery ground goes directly to the block at the starter...)). 

The engine is a very "noisy" environment - electrically speaking. Some equipment needs to be wired using shielded cable and the shield needs to be grounded only on one if it's ends to eliminate as much noise as possible for the sensors to report properly. This all should have been in the Haltech wiring information. 

We installed ITB's on the Swiss 240Z and Tony at UMS here in Phoenix installed and tuned an AEM infinity ECU. It made decent power for a mostly stock engine (mild cam) -  180 RWHP.

Edited March 29, 2022 by cgsheen1

[Blitzed]

Thanks for the response and info. 

Moved the star ground from the chassis to the head and the issue with the hall effect signals gone. Haltech signal grounds are all connected to the main battery ground, correct the trigger and sync are shielded cables (2). Haltech suggested adding grounds to reduce the noise on the block. 

ITB's, coil and hall effect distributor are AUS based products. Straight forward install the hurdles have been ECU functions. All good now, starts, idles, all outputs on the CAN look good. Working through transient throttle tuning or additional vacuum sync on the ITB's, she's coughing (no backfire) though the ITB's when stabbing the pedal. 

Encouraged by your HP gains. I'll enjoy the stock L28 this year. Pull the engine end of year to stroke and head work (N42 head). Wanted to understand the ECU / EFI conversion before the rebuild and reinstall. 

Enjoy the drive.

[Blitzed]

Hi All,

Still having  issues with the connection from the ECU to laptop while driving. Very random, not at specific rpm or load. Can turn on and off components (lights, turn sigs, radio, heater etc..). Will stay connected on a drive for 20-30 mins then disconnects, next drive disconnects every 5 mins multiple times, then stays connected for the remainder of the drive.

Where is the noise coming from randomly? 

Specs: L28 73 240Z stock wiring harness with a Haltech 750 ECU, ITB's, single HEI coil, sequential fire with a modern electronic distributor (sync and home signals), in-tank fuel pump (static speed) . I've grounded every thing to the block and added grounds, shorten the ground loops, coil , distributor, and intake. Cleaned and reinstalled all stock ground locations, upgraded the alternator with diode connector (removed the stock VR). Added a suppressor to the coil positive, removed and installed the 2.2mf condenser, removed and installed a 3.0mf condenser and replaced the laptop and com cable (twice), going broke. 

Here's an unusual questions. Can the fan clutch noise create any interference with an ECU connection or an electronic distributor?

Any suggestions? Thank you. 

[gundee]

Maybe this MSD 8830 noise filter can help if you suspect that issue. When running a MSD ignition it does the following.

When the MSD draws current, it will draw through the Noise Filter instead of directly from the battery, so all other accessories that operate off 12 volts, like the radio, fuel pump, or the engine computer, will be unaffected by the MSD.

 

 

[Blitzed]

Hi Gundee,

Will check it out. Not sure the installation as I'm not running a MSD module. 

Ignition set-up ECU coil wire to a small ignitor module to the single HEI coil (ignitor and coil pic in thread). Can add filters at the coil and have been trying different configs. MSD is a ignition module so the installation could be similar. 

Suspect you're right the com loss could be battery voltage changes as Haltech installation instruction have the main ECU connections to the + /- of the battery. That all runs through a relay and fuse box to the ECU and harness. 

Check and see if I can data log batt voltage on my next drive and check for any changes in voltage when the com goes down. 

Thanks for the info.