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Re: VS S3 Manual Log - Problems Or Normal
Posted: Thu May 03, 2012 1:29 pm
by Holden202T
There should be a table in the tune for Lean Cruise, have a look at it, it will tell you at what load it will be in lean cruise ....
usually they are light throttle and at certain rpms ... as you push the go pedal more lean cruise slowly richens back up to the normal 14.7 .... you should be able to see that in the logs if you look.
Re: VS S3 Manual Log - Problems Or Normal
Posted: Thu May 03, 2012 9:39 pm
by Monarols71
Thanks Holden 202.
Does this look like a normal lean cruise table to you clever people.
I'm guessing the left vertical column is RPM, but what is the top horizontal column?
I've googled "air fuel delta vs rpm & cylair", but I haven't found anything that really explains it to a dumb arse like me.
Kind Regards
Re: VS S3 Manual Log - Problems Or Normal
Posted: Thu May 03, 2012 11:54 pm
by charlay86
It is mass of air in each cylinder, which is used to determine the load on the engine.
Re: VS S3 Manual Log - Problems Or Normal
Posted: Fri May 04, 2012 6:11 am
by yoda69
The values in the table are added to the stoich AFR (14.7), so a value of 1 in the table means target value of 15.7.
Delta means difference between 2 known values or change from a known value as is the case here, and is a fairly common engineering term, ie temperature delta, pressure delta, etc. the symbol often used is a triangle, which is capital D in Greek alphabet.
Yoda69
Re: VS S3 Manual Log - Problems Or Normal
Posted: Fri May 04, 2012 4:59 pm
by Monarols71
Thank you both for that. That chart makes a whole lot of sense now.
I thought with the AFR being all over the place like it was in the log that the O2 sensor was NFG.
I've cleaned the IAC and the ports for it in the throttle body. Didn't seem too bad, but it's done now.
I'll try driving it with the O2 sensor disconnected and see what happens.
Thank you all very much. Now for some more logs and