First ElanScan Drive with logging

[jc_uk]

Hi all,

I have latest published version of ElanScan now working with my homemade USB cable.

ECU file attached but renamed to Zip - not zip file....

The drive started off with several minutes of idle before driving from home up to local A roads and dual carriageways etc for a loop back to home.

Would be good if anyone can have a look at the logs and highlight any issues you may see.

Currently having problems with exhaust popping/banging on overrun and probably running too rich, etc.

Trying to diagnose the problem(s) to work out what needs to fixed/replaced.......

Do I also ned to run in Test Mode?

Many thanks in advance

JC

[chrism]

Anyone else not able to open this file apart from me? I keep getting 'invalid file'...

[jc_uk]

Hi all,

Try the attached, ecu file added to a compressed folder/zip archive.....

Many thanks

JC

[chrism]

Yep, this has worked. Had a quick look + can't see anything obviously amiss.
Was this the same data with a warm-up period?

[jc_uk]

Hi again,

Yes, warm up period is at the start of the log......

Many thanks

JC

[chrism]

I tend to only look at warm-ups - since things tend to change under driving conditions - and I've superimposed some of my own warm-up data in black. I'm no means an expert and my own '90 m100 might not be perfect but I see you're 9930/closed loop.

It looks like your warm-up spark advance averages around 23*- imo a little high, mine's ~15/16*

Your warm-up air:fuel ratio is a little rich. My '90 SE is closed loop, with an O2 sensor, takes around 3mins to warm-up then settles to 14.7:1 - yours settles after nearly 7mins to a tiny bit on the rich side and, I presume, can be adjusted using the rheostat/pot near the ecu.

Perhaps these could cause exhaust 'pops' but afaik your exhaust equally could be guilty?

Other than that I'm not 'EScan-expert' enough to say more. I'm hoping one of our LEC 'gurus' might be able to look at your scan and add to our learning experience by fleshing out these tiny bones.

ps I gather (paper-clip) test mode turns off sensors so's you can adjust stuff statically, but I've never got mine to start in test mode...I'm not sure whether it should or not; perhaps someone can advise?

[Fredjohn]

Just a quick correction. Once you go closed loop (or already are) with O² sensor, the potentiometer by the ECU is redundant.
If it's running slightly rich, you will need to look at other aspects of fuelling. O² sensor, CTS, injectors, timing.
I'm sure others will post with more detailed ideas.

[chrism]

Sorry Fredjohn, my mistake in the previous post...jc_uk is currently prom id 9930/open loop...

As you correctly say, if/when he goes closed loop (edit:- by adding an O2 sensor) the fuel adj will be continually made by the ecu and the pot will consequently be made redundant.

Sorry to cause confusion...

[dapinky]

Just to add to the confusion - even with an O2 sensor and a 'closed loop' map, the car will still start and run in 'open loop' mode until the temperature reaches the level that it swaps across to using the Lambda value presented by the O2 sensor..... I don't know if the 2 systems have exactly the same inputs in the initial stages, or if they are different.

[Tuga2112]

based on the discussion so far,

some things come to mind
CO pot. may be set to overfuel
CTS may be reading too low temperature (something elanscan would tell)
an injector or more is/are partially clogged and closing too late causing overfuel (bottle of redex may help)
fuel pressure regulator fault (not common from what i have noticed in the past)
bad sparks. which woud lead down the rabit hole of plugs, leads and coils. but also seems unlikely.

personally

1 - look at temp readings from CTS in elanscan. do they seem right ? if not. how far out are they ?
2 - the mention about the advance being too high (23degrees?) is something i would look into first,
i would look into setting the timing to 16btdc and see if its right, or too far out, and if the HES needs to be at the end of its adjustment to reach 16btc then i would consider exhaust cam could be out of alignment. i would set that up just because it seems odd, (but not necessarily wrong) and its free to check.
3 - look at the CO pot (or consider upgrade to close loop) for adjustment

[chrism]

dapinky, the black str line trace at 14.5:1 is the a:f ratio from a pal whose '94 S2 had a broken O2 sensor - from cold.

the blue trace - from cold - is after we installed a new one. Note that the start up rich mixture of ~12:1
gradually weakens towards 14.7:1 as temp rises...

and the pink trace is jc_uk's - again from cold. A 14:1 str line 'til it's warm enough at 14.5:1 set by his fuel
pot(?) then he drives it...

From this limited data my thoughts are that w/out an O2 sensor the S2 uses a default 14.5:1 ratio and the SE is defaulted to 14.0:1. But with a healthy sensor the a:f ratio starts 'rich' at around 12:1, then weakens to 14.7:1. As you say, these phases will be open loop until the ecu is told by the temp sensor that it's warm enough.

It seems that when the (healthy) O2 sensor tip is heated up sufficiently - with the help of its own heater - it snaps into closed loop at 14.7:1. If broken it might stay at 14.5:1 until the temp sensor takes over to tell the ecu that engine is warm enough and I (should have logged longer but...) presume that it, too, should snap into closed loop.

I have the impression that jc_uk doesn't have an O2 sensor (since he has a 9930 prom) so I suspect his a:f ratio might default at 14.0:1, then snap into the fuel pot adjustment of 14.5:1, in his case, when the temp sensor tells the ecu that the engine is warm enough.

I wonder if this implies that the 2 systems are different due to non-O2 sensor default vs continual O2 sensor adjustment? That broken O2 sensor data might provide the clue?

In any case...I still reckon jc_uk's popping might be exacerbated by mis-timing?

And Tuga that's a lot more flesh welcomed to the bones, thanks.

[Tuga2112]

Chris,
this may come across arrogant and dismissive of your efforts, so, i am trying my best to put it in factual form. with a big caveat that is purely my opinion/educated guess, based on limited understanding of the car or ECU designs, with a fair amount of educated guesses based on self taught understading of electronics and I dare say, a good understading of software engineering, topped up with my memory of what sensors are present in a open loop car. that are related to the combustion.

so, please bear with my thoughts.

I believe the air/fuel ratios from your reading are as accurate as the elanscan "gear" data. (purely guesswork by the computer.)

I would advise to completly discard them as they are calculated figures and not extracted from any sensor,
the air-fuel ratio specifically on a openloop car (no o2 sensor influence)
I would guess is probably a calculation based on the time the injectors are 'told' to being open (clogged injector would not be taken into account), with a fixed fuel pressure (assuming the fuel pressure regulator is working correctly), and the reading from the MAP + air temp sensor (estimated 'oxigen amount', by calculation based on pressure, temperature and assumption of x% of that being useful O2).
2 of those parameters are not actually controlled by a sensor.

even on a closed loop. the o2 sensor wouldnt know the tair fuel mixture, it would only know the amount of unburned fuel, which again can be incorrectly estimated based on the fact the computer doesnt know if the fuel pressure is right.

I rather look at the readings from the things that are directly controlled (or report to) the computer (sparks, MAP, O2 sensor, CAS and CTS) because these are the building blocks the ECU works with.

and i do apologise for that, because i dont have the time to look into the raw data and try to figure out where a discrepancy may be occuring, I honestly do not believe to have the skill or insignt to do such (at this point in time), and would probably end up just comparing "good run" readings with "bad run" and hope to find something obviously different to lead the investigation further and theorise potential places to look into.

[chrism]

Hey not offended Tuga - and no apologies needed.

I was just trying to find some differences between open loop and closed loop initial start-up data - since dapinky posed an interesting point. The air:fuel ratio seemed to me to give a clue and I took its accuracy in good faith.

I tried to use what data I have, I don't have non-O2 sensor data and saw a similarity with what I know to be a non-functioning 1499 O2 sensor and what I suspect is jc_uk's 9930 non-O2 sensor data.

These superimposed data sets also serve to show that the closed loop/O2 sensor system enriches the air:fuel ratio on start up, as well as keeping it 'honest' on the 14.7:1 sweet spot when it warms up - thus vastly reducing MoT emissions stress. Imo totally worth the conversion for SE non-O2 sensored owners.

We shouldn't hijack response to jc_uk's post tho'. I'd be interested to know further details of his m100 (also where he's based?) and whether timing adjustment solves his exhaust pop.

[jc_uk]

Hi all,

I have been doing some more forum reading and I've also found a paperclip to get into diagnostics mode......

With the black and white cables on the ALDL connector are shorted together I see the 12 flashed out on the engine light,

When I run the engine in Diagnostics mode the engine runs very rough and soon stalls....... very different from normal run mode......

I don't think the garage that services knows about the Diagnostics mode (yet....)

So I think it is back to the basics and working through the flow charts and timing in the Lotus Engine Service Manual......
And get the paperclip out.

Many thanks
JC

[jc_uk]

Hi again,

Some background info

My M100 is H reg and I have owned it since 6 months old......
Currently at ~95,000 miles
It is an Elan SE Turbo and pretty much original.......

I'm based in South Lakes/Cumbria, nr Kendal.

Many thanks
JC

[chrism]

So, no O2 sensor confirmed. This might seem to support my air:fuel ratio thoughts, but yours is the only EScan atm that I know of w/out an O2 sensor. I could do with an a:f ratio for at least one more (non-1499)...any takers, please?

I gather code 12 means nothing is wrong and certainly mine doesn't even start up in diagnostics mode. I think this mode disconnects sensor input and I expect this'll 'distress' smooth running. Perhaps a guru can advise?

I think follow the Tuga advice first - he says sparks are one of the ecu's building blocks - and set the timing to 16*btdc in normal mode, try it out to see if it still pops + bangs then let's see another EScan - I think just a warm-up will suffice to show timing advance. (It'd be rude not to now that you know how to share the data ) Plus I'd like to see your warming up temp unaffected by airflow to see what temp the thermostat is opening...

I must admit I haven't needed to do this yet so I don't know whether diagnostics or normal mode is appropriate; I reckon I'd need normal so the engine would need to be running...

I think I'd be inclined to try to set it statically in diagnostics mode and/or check it running in normal mode - although 'Wheeler Dealers' had Edd turning the CAS by hand and Mike under the w/arch reading the timing light with the engine running if I remember correctly.

[Fredjohn]

Don't forget you also use the paper clip and ALDL socket for service mode.
Think it's time to get the WSM out!

[dapinky]

...... but yours is the only EScan atm that I know of w/out an O2 sensor. I could do with an a:f ratio for at least one more (non-1499)...any takers, please?

You called, sir?

As luck would have it, I am a bit of a hoarder, and that includes old HDDs from very old laptops (ok, so I keep them for the "value" of knowing where any old sensitive data could possibly get to, not because I want them in the loft).....

....I have a folder entitled "ES runs" from 2008/9/10 era....... some are mine, some are other peoples - there are 9929, 9930, and 1499 memcal results amongst them...... some are runs without any known problems, some are runs with known problems (on the way back from MOT failure for stupidly high HC levels caused by a HG failure).... followed by runs on the new engine.

Much of the data means little to me, as I am no expert - but you are welcome to take what you wish from any of them, and see if it may help your deliberations.... there is even one from a little 'scenic drive' over the Mountain Route on the Isle of Man, just in case changes in atmospheric pressure and right foot weight may be of use to you in interpreting data.

old es runs.zip

[chrism]

Thank you dapinky - your data means itch duly scratched re diff between warm up for non-O2 and O2 sensors:-



Pink trace is a:f ratio for a healthy promid 1499 O2 sensor, blue + black traces are for promid 9930 + 9239 non-O2 sensors

The non O2's seem to have a constant/default a:f ratio at start-up probably set by the fuel pot + ecu and the O2 starts from an enriched status, but gradually weakening as temp increases until the magic 14.7:1 optimum ratio kicks in.

I wonder if this helps out with your "I don't know if the 2 systems have exactly the same inputs in the initial stages, or if they are different" thoughts?

(ps does Mrs dapinky know about that trip to your local common in the middle of the night? )
(pps still looking forward to jk_uk's corrected timing advance data so as not to hijack his thread.)

[Tuga2112]

(pps still looking forward to jk_uk's corrected timing advance data so as not to hijack his thread.)

this may be a problem. if i understood a previous message correctly the engine wont stay alive when in diagnostics mode. setting the timing would be very challenging, maybe even impossible