File Review Request

[NoahR]

Hi everyone,

Would someone mind taking a look at my attached ElanScan file and checking for anything that doesn't look right?

I've just done a closed-loop conversion (wiring all already in place by the seems of it). This was done mostly at idle around the car park, as the car still doesn't have an MOT - I revved it a bit and drove it around a little. There's still lots of white smoke coming out of the exhaust, but I'm hoping this is still due to the car not having been driven in so long.

https://drive.google.com/drive/folders/ ... sp=sharing

Thank you in advance!

Noah.

[Fredjohn]

Don't forget the turbo only kicks in above certain revs and only once engine warmed up.
Elanscan will still scan, but won't effectively show any closed loop readings.

[NoahR]

Thanks Fredjohn. I assume it would still show that the closed loop was functioning properly? E.g. the Oxygoen sensor readings, etc.

[Fredjohn]

Yes correct, once it has warmed up.

[KenS]

Had a quick look at your ElanScan file and it does show its running in closed loop. The plot of CO Pot/Oxygen Sensor Voltage shows the voltage is very active, indicating that the O2 sensor is working and tracking the exhaust gasses, if it was still in open loop, this voltage would be static as set by the old CO Pot or a default value if it didn't get warm enough to enter closed loop mode.

Screenshot 2026-01-17 214330.jpg

Also, the Air/Fuel ratio is very well controlled at about 14.7 which is the optimum value and achieved by the the ECU in response to the O2 sensor value, again a good indication that closed loop is working well.

Screenshot 2026-01-17 214409.jpg

I have not looked any deeper but so far it looks good. I'll try to have a more general look if I get some time, maybe ChrisM will have some input, he is great at diagnosing and comparing these plots.

[NoahR]

Brilliant, thank you so much for taking a look Ken!

On this thread, I've mentioned some issues with white smoke coming out of potentially the alternator - viewtopic.php?f=29&t=30579&p=385201#p385201 - is there anything voltage wise thats worth looking at on Elanscan to indicate if it is an alternator issue (its unclear where the smoke is actually coming from).

Thanks again!

[KenS]

A bit odd, the plot for battery voltage does look a bit low, not going above 12.5V, I would expect it to be more in the 13 - 14V region, but also dont think the alternator regulator issue with O2 sensor load is directly evident here. Normal observations with that issue is that the ignition warning light comes on with engine running and cannot achieve the full 12V at the O2 sensor heater pins, which doesn't seem to be the case here.

Screenshot 2026-01-17 221337.jpg

I'll have a better look at the plots and think some more.

[NoahR]

Lovely, thank you Ken!

[chrism]

Hi NoahR, yep I reckon Ken's covered it all absolutely admirably.

I've overwritten your battery voltage with a couple of my own battery traces which are pink, green and black:- (why not? )



Interestingly I've downloaded your ecu file as 'run.ecu' whereas Ken's is 'run(1).ecu', and both of our downloads put your Prom id as '199' instead of '1499'. But in any case they're the same and you can see that my overwrites show 14V-ish whereas yours should, as Ken says, show 14V-ish when your engine's ticking over, instead of your 12V peak...(and slight oscillations?)

And again as Ken says*, the alternator red light also feeds the O2 sensor current and when there's a failure to supply enough current here then the ign red light comes on when the car's ticking over and the O2 sensor trace goes 'odd'. BUT your O2 sensor's firing up okay, according to EScan, so it seems to me that your alternator's providing enough current for the O2 sensor to warm up and work - but 'not putting out enough volts' to get the the 14V-ish expected that our cars reach on tickover?

* Paraphrasing KenS...

Just a thought - does your ign light behave normally, ie red (12V on dash voltmeter) at switch on then goes out at engine tickover (14V on dash voltmeter)?

I hope I'm not throwing in a red-herring; I wonder if any of our electrical/alternator 'gurus' can add some flesh...

ps And I wonder if EScan would have shown a peak at 12V on your open loop prom id before you converted to 1499 closed loop? A bit of a faff but you could still check this if you wanted..

[chrism]

...sorry, long-winded I know but also from reading your p/steering fluid post has your dash voltmeter never read 14.4V - but only 12V - on tickover even before you went closed loop?...

[NoahR]

Hi Chrism, thank you so much for having a look!

Interestingly I've downloaded your ecu file as 'run.ecu' whereas Ken's is 'run(1).ecu',

Perhaps Ken just duplicated the file by accident - either way, the data seems the same, yeah.

and both of our downloads put your Prom id as '199' instead of '1499'.

Yep, I've got the same on my ElanScan as well. I hadn't noticed that. Its the chip from RonR, so not sure if he could provide some input as well? I've looked at a log file from before I changed the chip, and it shows the Prom id as '9239'.

But in any case they're the same and you can see that my overwrites show 14V-ish whereas yours should, as Ken says, show 14V-ish when your engine's ticking over, instead of your 12V peak...(and slight oscillations?)

Interesting, that makes sense. I've looked at a brief ElanScan file from before I did the changes, and it also shows battery volts at or below 12v. So perhaps I've got a separate issue, not linked to the o2 sensor. Could a bad battery cause this?




I've linked the old ElanScan file (lotusV2) here - https://drive.google.com/drive/folders/ ... sp=sharing.

Just a thought - does your ign light behave normally, ie red (12V on dash voltmeter) at switch on then goes out at engine tickover (14V on dash voltmeter)?

Just checked, and put a video in the linked folder. Is this what you meant/is this normal behaviour?

Does that answer everything? But yes, now I'm thinking about it, I think its always been approx 12v - also as shown by Elanscan, even before going closed loop. - I don't think it ever went up to 14v (only had the car since end of sept.)

The car has an external immobiliser fitted, in case that's useful information.

Thanks!

[RonR]

both of our downloads put your Prom id as '199' instead of '1499'.

Ah yes,

Prom ID = 199 is the standard version of 1499 - I've started to code the PromID in my boards to make identification of mountain chips easier, as Alan did on his 16-prom switcher boards. My codes are:

PromIDs.jpg

[NoahR]

both of our downloads put your Prom id as '199' instead of '1499'.

Ah yes,

Prom ID = 199 is the standard version of 1499 - I've started to code the PromID in my boards to make identification of mountain chips easier, as Alan did on his 16-prom switcher boards. My codes are:

PromIDs.jpg

Thanks Ron. Does the Prom ID switch then when you switch the jumper between standard and mountain tuning?

[RonR]

Thanks Ron. Does the Prom ID switch then when you switch the jumper between standard and mountain tuning?

Yes it does, if you display a graph of PromID in Elanscan you'll be able to tell which prom was active at any time, and when you switched between them.

[chrism]

Yep I reckon the start-up lights are all okay on the video, and the red light goes out as per normal

Your p/steering fluid/alternator link mentioned about smoke being seen after RonR's upgrade and I bet that's an unfortunate coincidence/link.

It's true that the fluid could be burning off something(?) It also seems from your earlier EScan that your alternator output hasn't been all it could be - but that your recent EScan focus, as a result of the upgrade, has highlighted this.

I'm thinking that I'm not sure a 'bad battery' would do this but could the alternator regulator be 'struggling' in some way? They are replaceable and there's posts on LEC outlining recent problems about suitability because 2 types fitted and only 1 worked O2 sensors for S1 owners and SE upgraders:



In the fairly recent past owners were replacing their alternators with pattern parts (originals not available) and noticing that the red ign light wouldn't go out on S1s and SE upgrades with O2 sensors. Indeed, some were shelving their new alternators and only fitting them after the guarantee expired - causing rancour due to a lack of interest after complaint to the supplier. Others were advising sticking black insulating tape over the red light

Thank goodness that our suppliers now seem to be wise to the difference after this 'error' was effectively sorted by Ken, Ron, Tuga and other gurus...

[NoahR]

Thank you for the thoughts Chris!

What leads you to think that it's only the regulator having an issue and not the whole alternator? - Genuinely asking as I have no clue haha. Is it due to the low power output? But then could the smoke indicate an issue elsewhere in the alternator? Interesting that its only started smoking now, even though the volts are consistent.

Then, is there a risk of damaging other electrical components if I keep running the car as is, and don't upgrade/change parts? - All with the aim of confirming if the smoke is actually coming from the alternator and not something else.

I have read/watched a lot on changing the alternator and on changing the regulator, so it doesn't look like the end of the world, but another job to add to the list if needed. - I've seen some of the bits on one from RockAuto with a longer belt, but need todo some more investigating. I've also seen a separate thread where someone else had the same 12v issue and it was just due to the green clip not being plugged in properly - fingers crossed.

Sorry for all the questions!

[NoahR]

Totally seperate to the voltage issue, I had a few moments while the car was at idle where it shuddered for a second and felt like it was about to die, then it was fine again. Any thoughts on that? On ElanScan, it looks like the revs drop occasionally - weird though consistent the rest of the idle is consistent.

[KenS]

Just to add agreement with Chris.
The battery voltage is low, the alternator is struggling to get the voltage up to its target of around 14V either poor regulation or insufficient current capability. Worth checking the alternator connections/earths - that round plug to the alternator can be difficult to push fully home. If you had access to another battery it would be worth a temporary swap to be absolutely sure its not the battery, but seems unlikely.
The smoke was most likely the power steering fluid on the exhaust (wouldn't be fluid on the fan belt causing it to slip and heatup?).
Probably not worth getting to deep or concerned, but there is an unexplained period in the log file, where the logging data seems to have stopped for 20 or 30 seconds (point A in copy of plots below), then about 40 secs after that the battery voltage drops below 11V (point B) then slowly recovers to near 12V. Do you recall anything that could relate to these, were the lights switched on? That event seems to have caused the ECU to shift the timing back a few degrees and have a slight effect on the IAC. Maybe its all just an effect of the low supply voltage. Problem with all these plots is trying to read too much into the detail and then struggling in knowing if its a cause or an effect, but its fun trying to be an armchair detective!

Screenshot 2026-01-18 192112.jpg

[NoahR]

Interesting Chris, thank you for your thoughts as well.

That would make sense about the smoke - a slight relief.

I don't have another battery, about unforutnately. Would a multimeter test not do the job?

With regards to the data, that's a good spot! I did turn the lights on at one point, including the full beams and hazard lights, so it may be that. My laptop also locked itself, so perhaps it was that, although given the cause and effect, that seems less likely to be the case.

I wonder then, if the smoke isn't coming from the alternator, and the car runs 'fine' to what extent it could all just be left alone...

Thanks for the support so far everyone!

[NoahR]

Incase its of any use, I've spoken with my dad, who owned the car since 96', and he always remembers the voltage being circa 12v - interesting...