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My 06 Elise 111R TVS1320 supercharged has been back on the road for a few months, thanks to people who helped me heaps on my valve issue, especially @MrWong. :smile2: I took it to the Phillip Island circuit late last year and looking to do a circuit called Winton in a couple of weeks.

Now onto some mystery.

I saved a ECU dump back in November as a backup and also a baseline. I didn't touched the ECU since.

I put in a AEM Uego wideband to help with tuning. I did a few 3rd gear WOT runs (results attached, yes I forgot to disable traction control but based on the slip, don't think it made much of a difference). I made sure the AFRs and temp was ok before I did the WOTs. The AFR was pretty much 14.6 to 14.8 when idling towards the place.

My mate who's very capable at tuning then did a cold start check (results also attached but fuel 1 was played around with during that time). What was odd was the AFR readings were at 11s. No wonder I was blowing black soot out always when cold.

He played around with the Fuel 1 numbers in the Fuel 1 map to bring it close back to 14.7. But we found it strange that the target AFRs 0% load @ 1000 and 3000 rpms was set to 10.0.

After he played around with it a bit more and found that the values did not revert back after turning off the car and back on again, I reloaded the November map. But to my surprise, the 1000 and 3000 rpm values for target AFRs was actually 14.7!!!??? Also I now have a few more warnings that wasn't there when we were doing the cold start checks.

I just did another cold check and the target AFRs have remained at 14.7 for 0% load.

Some questions:

1) What could change target AFR values? I didn't touch them since November. I assume tuning the fuel 1 numbers don't change the targets?
2) No matter how long we had the car warmed up during cold start checking, we couldn't get it the car to change from the 13.0 AFR target to 14.7. Whereas during driving to the WOT runs and before hand, 14.7 was the target. We looked at all the corrections but couldn't undertand why it was trimming, eg. battery, MAT, WT, TPS.
3) Does the SSC ECU like to cold start rich?
 

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Couple of things....

Changes that are made to the file while connected to the ecu are hard changes and nothing will revert back if the car is turned off.

All cold start changes should be addressed in the corrections tab since those are made on top of what is in the tuning tab. The reason it probably runs rich during cold start is due to the corrections. It should be richer than stoich during cold start.

The values in the tuning tab should really only be changes when there are no corrections being made, i.e. open loop, and car at operating temperature.

The afr target will not randomly change, sounds like the current ecu file had the wrong values there but the november file had the correct ones.

The warnings in the afr tab are there because you don't have the wideband connected to the ecu and the narrow band can't read those values. If the wideband is connected then you need to set the ecu up for it. If you are trying to run closed loop all the time with just the narrowband it is not going to work right.

You can send me your ECU file if you want. Just PM me your email.

In your cold start and idle data log, were the targets in those two cells still set at 10.0 afr?



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You can send me your ECU file if you want. Just PM me your email.

In your cold start and idle data log, were the targets in those two cells still set at 10.0 afr?
Hey @ScottH83! Thanks for your replies and advice. PM coming your way.

For the cold start log, the targets for 2 cells were set at 10.0 AFR but I hadn't touched them since the Nov dump and no one else has access my ECU. All we did was change the fuel 1 map where the cross hairs were.
 

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SSC ECU also has "adaptive tuning mode" in which it will start to adjust the fuel table cells as it runs. If you're seeing changes in your table, check to make sure it's not in adaptive mode and in fact in closed loop.
 
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