I learn something everyday. I didn't know it was in the dash. Thank you for that.

 

I'll be reading more into this. I just won a terminator x max in a raffle and im trying to figure out how to keep factory gauges (mostly concerned about the odometer) and pass Texas state inspection.

 

I talked to Jolt this morning. He is going to start doing this full time next week. He will announce when preorders are available and will only take a certain number at a time. Which honestly I think is a good idea.

The Jolt harness is a "trimmed down" factory harness with needed connections to keep the rest of the car working. The Holley harness is integrated into that, so there is no need to buy a main harness.

The stock PCM stays in its location. The harness is long enough to put the Holley ECU behind the glove box or behind the passenger kick panel.

As long as the work is quality, I told him he should have no problems staying busy.

 

That is a cool idea. I considered it but the time I had invested in the harness, I would lose money at a price point I think it would sell

 

Definitely interested in seeing how that turns out once they finally release. I have wanted to Holley swap my car for a long time and gauges was a big hangup for the swap.

 

@Darth_V8r - what was the Jegs' kit you are referring to in your second post. One of the LS harnesses? thanks

 

Sorry to kind of leave this one hanging temporarily. I had three solid weeks of business travel, and NONE of it went as planned. I've finally got a chance this afternoon to try to get everything pieced back together. I doubt it'll get running, but I think I can get all the electrics properly run.

The kit is used is a loom kit. Part number is 555-10659. I used the factory wires - just straightened them out and rebundled them how I felt they would run best through the engine bay. I figure if it doesn't work I can always just get the current performance harness. I just kind of wanted to try it myself. Mainly because I was scared to try it, and I don't like being afraid of anything. Face your fear kind of thing.

But honestly, I think it will work just fine. My biggest thing is I think I messed up on how I routed the coolant temp sensor and the evap connectors. if I have to, I'll leave the evap unplugged so I can test out the coolant temp triggering the fans. If that doesn't work out like I hope, then I think I can figure out how to make the holley trigger the fans for me. Just gotta ID the right wire on the chassis side. And that info is out there. I've seen it in various threads.

 

I finally, finally FINALLY got the car running yesterday (Dec 31). There is something not right about the crank signal. I'm using a 58x/4x reluctor. The holley runs the 58x natively. the car ecu runs 24x. so I'm still using the lingenfelter box to translate the signal for the stock ecu. it isn't happy about something. when I crank, the rpm goes negative not positive. then when it runs, the rpm stays zero. The good news is, no smoke!

To avoid sending people down the re-read rabbit hole, the first swap to the current heads, I missed a lifter cup, and the pushrod bent, scissored the link bar, which broke it, and punched a hole in the intake runner of the head to the intake galley. We patched the head with epoxy, but during the inspection process, we found that the motor was junked, so we built a whole new bottom end. After getting it up and running, the car dyno'd 693 at the tires NA, but the motor was smoking like a chimney. Upon further inspection, we found that the epoxy patch had not fully sealed, and was sucking oil into the running. But I was smart and put the patched head on the driver side so it was easier to pull just in case. While the head was off to be re-patched, I decided to swap over to the Holley ECU. Mechanically, everything was back together other than a few odds and ends. I hope that's enough backstory. Trying to stay on topic.

Initially, the car would crank but not start. Noid light found injectors not pulsing. Spare spark plug on the cylinder head found coils not firing. I missed the smaller red wire. I had run it in a loom to the batter, but had not hooked it up, and it fell out of sight. Hooked it to the battery, and the car would fire for a few seconds and die. Very quickly determined the fuel pump was not staying on after it started. The holley harness comes with a green FP trigger wire that you can tap into the C101 connecter - green and white wire on terminal D. I went ahead and did that to keep the fuel pump running, and sure enough, the car started and stayed running. The idle was actually tamer than it was on the stock ECU.

The holley software is very different from HPTuners / OE computer. There are tables altogether "missing" from the holley, but the tables that are present can be reconfigured easily. For example, on the VE table, you can just change the RPM and MAP axis values to whatever you want. It appears to be far less tricky to set it up for open loop idle and closed loop cruising.

Anywho.... after I got the car running and idling, I let it warm up. everything on the stock gauge appears to be working except the tach - as I mentioned before, I think I have a crank signal issue. That aside, the other thing was the cooling fans did not come on. I believe that - similar to the fuel pump - the ecu does not see the car as "running" so it is not controlling the fans properly. I might chase this down a little bit, but if I cannot solve it quickly, I will run a separate trigger wire from the holley to the stock wiring harness and let the holley control the fans. I have considered the possibility that it's just too much signal conversion with three different systems using the crank trigger, and if that's the case, then my stock harness experiment might be over. honestly, if both were 24x, i think it would have worked fine.

I'm sorry it was so long. I know I have owed you guys answers, and I finally have them - and some more work to do to iron it out.

 

Darth, this may be a back up to the back up plan, however if you run into the point of "no other option", you could always use a crank trigger to run the Holley, and use the OEM crank sensor for the box and the factory computer.

Another option to look at may be to use the Holley tach output (I know it's a blue/white wire on the 24x harness, I'd imagine it's the same loose wire on the 58x) through a signal conditioner into the OEM computer input, something like the Dakota Digital SGI-100BT.

I know that you can split a hall-effect signal without issues, but the 2-wire signals that use pulsed ground output can get sketchy.

 

You could use the holley tach output wire, But you would need some kind of digital conversion device to convert it to the 24x crank signal...fed back to the stock ecu crank input. Could do it with an arduino. Know anyone who does coding ?

 

That's a good idea with the Arduino provided (and I'm sure someone out there could) the coding skills. I mentioned the Dakota Digital SGI-100T because you can actually tweak it from a Bluetooth enabled app on your phone to dial in the signal.

 

Darth, pondering this a little more, how are you currently splitting the crank signal? I assume you are splitting it before the Lingenfelter box with the Tick harness and using the loose wire for the Holley, then using the box to output to the PCM and tach? Or are you using the Holley tach output to the factory gauge?

Additionally, to get oil pressure on the Holley too, you could always tee the factory OPSU and run a second LS type sender? Or tap the block off plate above the oil filter.

What's the intended purpose or desired end state for running the Holley, other than it being cool as hell to make it work? Performance goal, or built in data logging?

 

I'm using the tick crank signal splitter. Running one to the holley and the other to the lingenfelter. The lingenfelter is then outputting the converted signal to the stock ECU. I actually think I might have found the answer - tell me what you think. I assumed that the lingenfelter could convert the 58x signal independently of the cam reference signal. I'm now thinking it might need both to function properly. I did not split the cam signal.

Additionally, to get oil pressure on the Holley too, you could always tee the factory OPSU and run a second LS type sender? Or tap the block off plate above the oil filter. I had thought about both. In the end, I would need to pull the intake manifold to get to the harness to extend it, and the only reason I would need oil pressure to the holley is if I upgrade the dash. If I get to that point, I'll just ditch the stock ECU altogether anyway. I cannot describe to you how much I really do not want to pull the intake right now.

What's the intended purpose or desired end state for running the Holley, other than it being cool as hell to make it work? Performance goal, or built in data logging?[/QUOTE]

Basically, it's this... I was running a custom OS, scaled tune, on a 1999 ECU trying to control an 8000+ rpm motor, and it's reaching up on too many issues. I really just want this thing to be a good street car that I can drive to the track, hit a 9, get tossed, and drive home. A la drag week. And yes, the built in datalogging and the ability to run closed loop off a wideband. And the easy with which I can run open loop at idle, customizable tables, add additional features later on, etc

 

As I understand it, the 58x signal can be split. The 24x signal cannot. NO guarantee this is correct, but it is my understanding. That said... the holley is reading RPM, and the lingenfelter green light is blinking, which means it's seeing signal, so at least I can confirm that the 58x signal split is working fine.

 

I know that the lingenfelter box reads both signals, I think you need both for the OEM computer to be happy.

So, looking at them a little more, the cam and crank sensors are both hall effect and not VR. From what I have read, the biggest difference between the 24x and 58x was going from a 12v to a 5v signal, I'm assuming that's all the Lingenfelter box is actually doing, stepping up/converting a 5v to a 12v. With all that being said, you could probably get one of those LS2 cam sensor relocation harnesses, or something similar to cut into, identify the signal reference wire from the Holley wiring, and split the cam signal in the same fashion that you did with the crank sensor.

I'm curious as to the "tuning" that will need to happen with the OEM computer, are there any special considerations to keep it happy without it having the ability to make changes? Essentially it's just a monitor, however if something is set outside of its parameters on the Holley, do you have to re-tune the OEM computer?

 

The OEM computer only needs the crank signal. On the 24x/1x ECU, the cam sensor only exists to tell it which cycle it's on. So, without the cam sensor, the ECU will try one way, after a second it will swap to the other way, and the car will fire. I can tell the stock ECU to ignore the cam sensor error. On further investigation, I found that the blinking green light on the lingenfelter means "Hey, idiot, I need the cam signal". I may try to tap into it tonight and see if it will fix it.

I was reading up some also and found the same thing. I was really trying to avoid tapping into the harness, but I may not have a choice. I am not finding any cam signal splitters out there, but there are plenty of crank signal splitters. Ideally, I'd rather have a splitter so I can remove it if it does not work. I might go to autozone and see if they have the pigtails and make one.

Understand, everything I'm about to type is a combination of reading other, smarter people's posts and experiences, combined with what I've found so far:

By removing all the wires, the ECU will not see any sensor used to control the engine -- map, tps, iat, etc, so all those codes will be set. The ECU also will still internally switch for the spark and injector firing, but the switches won't go anywhere. This might mean I need to adjust all the misfire tables, because the engine won't act according to the stock ECU's commands. But as long as the stock ECU sees the crank signal, despite a severely high number of codes, it will see the engine is running and "assume" it is running the engine. So my plan is to simply disable all the codes that show up after the ECU is responding properly.

I figure that if this fix works, and I see the OE tach responding properly, I will let it warm up, and see if the cooling fans fire like they should. If they do, then I will know that the stock ECU is happy and I'll start disabling codes. I want to wait so I don't disable something I need to leave enabled, if that makes any sense.

 

That makes sense on a 24x, but wouldn't it reduce resolution without getting a tdc pulse every 360 degrees? If the cam is spinning at 50% of the cam, that 1x pulse should just be telling the computer that it's confiming one complete cycle?

I think that both sensors use a 3 pin metripack, there might be different tabs inside the connectors to keep from plugging one into the other, but you could either buy the same splitter and file out the tabs (obviously verify the pins) to fit the cam, or get the same splitter and re-pin it with new connectors, or get a set of male and female metripack 3 pin connectors and make your own splitter harness. I would agree with you though, I would figure out an adapter solution and leave the Holley harness untouched.

So, basically you're going to tune/run the Holley, let the OEM computer throw whatever codes it wants, and just eliminate the codes one-by-one to ensure everything is happy, and leave only what's necessary to operate the "left over" OEM systems? What transmission does the car have?

 

The 1x pulse is basically 360 degrees crank (180 degrees cam) of 1 and 360 degrees crank (180 cam) of zero. --------_____--------_____. if you think of the firing order, the cam position 1 means cylinder 1 is on the compression / power stroke. The cam position zero means cylinder 6 is ont he compression / power stroke. Those could be backwards, but I think you get the idea. Without the cam sensor on the 24x/1x, it just tries using cyl1 first. if no fire, it switches to cylinder 6. I'm not 100% sure if the 58x/4x will do the same thing. There is a skip in the reluctor on the 24x, so it knows where the crank is on rotation. Same with the 58x.

That's my plan. I just found where I can go get some female connectors locally and make a splitter. Actually the cheapest way to do it is to buy two of the subharnesses unless I wait a few days.

Exactly. Manual transmission!

 

That makes sense. I would imagine then that the only potential detriment would be the tach not reading quick enough or losing resolution at the higher rpms, but as to it running, there would be no ill effects because the Holley is still getting a 4x cam signal.

I'm interested in the data.

9s in a three pedal street car, pretty stout for sure.

On another side note, do you still have ABS? If not, have you had any thoughts in trying to pull signals from the front and rear ABS sensors for VSS inputs to the Holley to be able to set up a more performance based traction control?

 

No I haven't. That's an interesting idea! I was thinking to simply split the VSS