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Looking for some guru swarmies to help me out in a jam.
I have thrown a 304 with a 4L60e into my LN106 Hilux.
I have rebuilt the engine with a mild cam, and had a go at building the 4L60e as well. Used a Marks Adapters housing to run into the original transfer case to keep it 4wd. Bought the NVRAM off here for Tunerpro RT- works a dream.

However,
it intermittenly throws a DTC 41 EST circuit short or open circuit and runs like a bag of shit, sometimes starting after leaving the battery unhooked, then only starting with some throttle.
I did some fault finding, pinning out the harness and making sure that i had continuity everywhere. I seen that the ignition module is often to blame, so i replaced that with a cheapy off eBay and viola, it worked, for a time.
Had had some dramas shortly after and wondered if the body of the ignition module needed ground. So i scraped some paint where i had mounted it (next to the alternator, under the air box) and it seemed like it was the end of that.

I have since taken it for a couple of test drives around the suburb, with dump pipes straight off the manifolds all seemed well. Half way through a trip to the exhaust shop to get the full system installed, it faulted again and ran like a bag of shit. Barely got it to the shop and it sits there now. Im wondering what to look at next.

Im using the original harness i got with the engine, 424 PCM, original CTS, MAT, TPS and IAC.
New proflow dizzy, Aeroflow Resin coil, new leads and sparkplugs, new-albeit cheap ignition module, new O2 and MAP sensors, SPAL 16" Push

Thinking it over maybe the ignition module is possibly getting hot where its located near the radiator?
I do have the harness earthed to the firewall, but i have 0.1 ohms back to battery negative?
Can i get interference from the spark plug leads off the dizzy if the harness is squashed up near it?

I attached 2 logs, first one would start up and then stall out.
Second one started and ran fine.

Another common fault and an easy one to check - sometimes the pins in the ignition module connector pull back and can cause intermittent issues.

Yeah ill give it a check when i go there today. It was running better when the ignition timing was in Bypass mode. Is there a way to keep it in bypass for the time being just to get it back?

If you just want to get it home you can bridge the diagnostic terminals same as you would when checking for DTCs or setting the ignition timing and will lock it at 10 degs.

I did try that today as well but more dramas arose. I checked all my wiring again to the ignition module, took the pins out of the ECM plug to crimp them a little so they were snug with the ECM pins, just in case. Even checked from the ECM pins onto the ECM board solder which was good.
Now there is no spark at the plugs and is hard convincing to start. I got it turning over but it sounded like it was firing on 1 or 2 cylinders at most. Wet plugs that were blackened up so i cleaned them up. Power at my coil and out of my coil, but nothing through the dizzy. The el' cheapo ignition module has power and good earth, even chucked the old one in for a laugh, but nothing.

A lot of people have problems with aftermarket ignition modules. You are often better off with another OEM one from the wreckers. If the connections are good, no corrosion or anything on the pins, and changing the module fixed it for a while, you could still have a new fault with the ebay module. Just a thought to keep in mind as you work through it.

antus wrote: ↑Fri Jun 07, 2024 6:37 pm A lot of people have problems with aftermarket ignition modules. You are often better off with another OEM one from the wreckers. If the connections are good, no corrosion or anything on the pins, and changing the module fixed it for a while, you could still have a new fault with the ebay module. Just a thought to keep in mind as you work through it.

Thanks antus yeah its in the back of my mind. Trying to get a hold of of another just to be sure.

Update:

Got the ute back from the shop this morning and had another go. I cleaned my plugs up and had a crank and it started first go. I didnt have brakeclean Friday and lung power was evidently not enough. Made a couple of logs and found im running rich af. Change Desired Idle VS Battery Voltage as it was stupid low at around 600. Seemed to run better as it was warming up but once the Coolant Temp and Manifold Temp started getting higher the O2 voltage climbed with it.

So this one is early in the log when it was warm
This one was eventually when it got warmer and the O2 was hitting 800+ mV and it got higher the longer i ran.
Also on the Engine Data gauges on the adx it was running at around 85-90 VE. If anyone could shed some light on why? I assume it has something to do with my milder cam?

I also had a look at my Scalers.
-Idle AFR vs Coolant temp
-Cold Engine AFR vs Coolant temp and MAP
-VE- MAP vs RPM
-Intial run AFR Offset vs Coolant temp

I understand the AFR is decided from multiple inputs, more than what im looking at but im not sure where i should start so i dont foul more plugs and call more towies.


Log attached also

Nothing really jumps out at me from the log, but I can see your narrowband voltage going higher, as you describe it, at the same injector pulse width (and map). I wonder if its actually you're o2 is getting more accurate as it warms up to operating temperature, and you just need some tuning to suit the cam. Its only a narrowband so it'll swing far from small changes, and if you havnt tuned it for the cam it might be time to get a wideband on it and warm it up and start tuning the VE.

antus wrote: ↑Mon Jun 10, 2024 7:10 pm Nothing really jumps out at me from the log, but I can see your narrowband voltage going higher, as you describe it, at the same injector pulse width (and map). I wonder if its actually you're o2 is getting more accurate as it warms up to operating temperature, and you just need some tuning to suit the cam. Its only a narrowband so it'll swing far from small changes, and if you havnt tuned it for the cam it might be time to get a wideband on it and warm it up and start tuning the VE.

Yeah id be keen to get a wideband and actually get balls deep into the tuning, but i'm parking it up for the last half of the year pretty soon (travelling). I was hoping there was an easy way to lean it out as an overall command just to run the engine in, but i'm starting to think you cant, or more-so probably shouldn't try that.
As for the DTC41 error code it seemed to have gone for now, but i haven't gone for a drive to be sure. The catch is i don't want to drive it rich as i haven't run the engine.