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  • 2 weeks later...

A/F Correct and A/F Learn will be your short term and long term fuel trims. These are the learnings of the ECU from closed loop O2 sensor feedback as to how wrong the "as mapped" fuelling is. Which is intended to account for problems with dirty injectors, engine condition change over time etc etc.

As to which is which..If I had to guess I'd say Correction was short term and Learn was long term.

Ignition is just ignition timing in degrees before top dead centre.

Alright sweet that makes sense, any idea how I could work out the ratio or should I just put an external A/F gauge in? Is the 85% on the A/F learn something I should be worried about? Been sitting at that since I first got the car at the start of the year.

8 hours ago, Inxlusion said:

Alright sweet that makes sense, any idea how I could work out the ratio or should I just put an external A/F gauge in? Is the 85% on the A/F learn something I should be worried about? Been sitting at that since I first got the car at the start of the year.

If you were keen to see what your air fuel ratio is, you're only real option is to install a wideband o2 sensor and a control unit/display/gauge. 

It's worth mentioning, if you were planning to buy an aftermarket ECU sometime in the future, I'd think about holding off on buying the wideband until you get the ECU. Then get the ECU with a built in wideband sensor or buy the associated CAN based sensor. 

The standalone wideband gauges can be plumbed into an aftermarket ECU, but they are a bit shit compared to a wideband that is operating over a CAN network or is built into the ECU (voltage offset errors are a nightmare, there is not fault reporting to the ECU, etc). 

Regarding the 82% learn reading, if the car is running fine otherwise, I wouldn't be too worried about it. The gauges aren't giving you enough information to be able to work out if there is something you should be worried about regarding the air/fuel mixtures. Getting the external wideband o2 gauge would give you the information you needed to work out if something was wrong with the AFR. 

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Not really to fussed about it not really to tune it or anything yet so not a priority just trying to work out what's what I guess. I have a gready emanage sitting there waiting to go in so I will look into how everyone's running their af gauge with them. 

Thanks for all the info everyone really appreciate it

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