Massive Over Fueling - Emerald

[Ferg]

Completed the wiring yesterday. A bit nerve racking as I only had two crimp connectors for the ECU plug, but they worked well first time.

As I had to run the wire through the engine bay it meant taking off the air intake pipe. This was half collapsed so not sure if this was restricting airflow but it was simple to reform and I also took the opportunity to clean and re-oil the air filter while I was there.

After setting the scale for the new input in the ECU config, it then started first time. The result was slightly unexpected but after letting the car get up to temperature the car is idling much much better. Now idling at 1k rpm, used to idle at 600 rpm. It also doesn't smell as fuel rich and when you blip the throttle it sounds quite different. The exhaust note is slightly 'thinner' if that makes any sense. I know a majority of those measures were subjective, but it is different. So I'm wondering if this points to the old narrow band sensor having issues. Going to get it out today and drive it a little to check it's not just a one off. Haven't messed with the fuelling just yet.

[2F45T4U]

Unlikely its the narrowband as all your adaptive mapping was turned off as was the closed loop so it wasnt having any effect.

The intake pipe would almost have to be closed entirely to have a much influence on the idle mixture but wouldnt have been helping anything.

What is the AFR at warm idle then?

[Ferg]

It's now sitting pretty much bang on at 15. Used to be off the chart.

[campbell]

Have you asked your Dad for the S1 back yet?!

I've thoroughly enjoyed reading this fable. Looking forward to the happy ending. And the moral!

[Ferg]

Moral is don't take the first MOT with an unknown car for granted. The rest is just normal S1 'character'.

Campbell, your S1 knows you cheated on her by going on Frolic with the Evora....

Back to the story....

I'm sitting in the old girl right now. Coolant almost up to temp, and lamba holding around 12.3-7. Its sitting at 800 RPM, I'm sure the neighbours love me right now.

[2F45T4U]

Still a bit rich. Will almost have to be bang on lambda 1 for a pass.
To give you an idea, the range on your test sheet for fast idle is between lambda 0.97 and 1.03 which is 14.3:1 to 15.1:1 AFR
Although lambda isnt measured at natural idle, if its not within the same range the CO and HC will be miles off.

Let the fan click on and click off. This is the point most testers do the emissions and should give you a repeatable point to base changes from.

[campbell]

Campbell, your S1 knows you cheated on her by going on Frolic with the Evora....

Au contraire, mon ami. My senior citizen S1 breathed an audible sigh of relief when the Evora was selected for Frolic duty. Remember she'd had to endure Spazz last summer. She still shakes at the mention of Zandvoort

[Ferg]

lol...yes indeed there wasn't a track on that trip she enjoyed too much.

I'm struggling to even affect the AFR. It's sitting at 12ish. Still way to high. Trying plus and minus ont he live screen affects fuel, timing etc in tandem. Trying to get the adaptive fueling to help out just now.

I also found an AC fuel adjustment enabled which I've switched of (AC disconnected).

[2F45T4U]

+&- only changes timing on the live screen
Changing timing will have an effect of the AFR but inly because youre changing the efficiency of the combustion, not because you're changing the volume of fuel injected.

2&3 changes fueling.
Press enter/return to write the trimmed value to the map.

You can use +&- to change fuel but only on the main inj map but you will need to write to ecu each time to see a change.

[Ferg]

Thanks, I keep telling myself to go back and RTFM. Easy to get sucked into try a bit here and a bit there...

I got adaptive mode running by widening the closed loop conditions. I had to allow a change of 40% before it would actually record some settings. It's been reducing the fuel by about 20% on average. I have a fast idle at 2k rpm thats showing 14.5 AFR. getting there. Its becoming more obvious that natural idle is a bit of a black art. What I don't understand is that the idle control is set to ask for 1000 rpm but its not doing this at all. Still to work that bit out.

slow progress, and then had a bit of a fright when it wouldn't start. ....I'd run out of fuel

[Ferg]

So...adaptive mode is very cool, but at idle rpm its not as effective. So used the manual mode and have got 14.4 at both natural idle and 1500 and 2000 rpm. Above that it's a bit hit or miss at a standstill and needs load. This will need someone in the passenger seat updating it while the car is moving. Going to get it tested at this.

I disabled adaptive mode around the idle related sites. Out of interest, for high load sites, is there a danger of leaving adaptive on all the time? Should it only be enabled for periods of tuning?

[steve_weegie]

Of course, I will happily volunteer to rag your car while you sit in the pax seat and map it

Ignition timing has a huge part to play on gas content - once you've got your fueling in the ballpark, you might need to tweak this during the MOT session, while the gas analyser is on the engine...

[Ferg]

I'm afraid I won't have the luxury of being in the car. Away with work first thing for most of the week.

We'll see either way mon/tues. If it passes I'll be bumbling around KH on Saturday and then seriously looking to get it properly mapped before double header in October.

[robin]

Ferg, cannot help much on the details of the mapping, etc., but you reported the exhaust sounding thinner - this is indeed what happens - richer mixtures are wetter/bass sort of sound and as you lean it out it becomes more mechanical/treble sound.

Cheers,
Robin

[Ferg]

SO, early reports are that it might well have passed the emissions.