COS 5 Question..

Also, I just noticed that IAT in B5911 is reported incorrectly. The IAT is recorded accurately in the log but when an area of the log is highlighted, the corresponding cells that are highlighted in the tune tool do not match.

I have always had problems with spark retard that does not make sense or I can't find.

It appears that only the tables that use or rely on IAT or ECT are affected.

Has anyone else had these issues? Do I have something set up wrong?

Thanks

Check that the scantool Data tab shows the same units for ECT as the tunetool table axis (i.e. both C or both F).

I don't know why the highlight won't match... check units between scantool Data tab and tootune table axis.

Ok, I'll check that. I did have them matched but I do remember changing part of the tune tool to Fahrenheit so I could understand it better. I very well may have left it that way.

Kind of a dumb question but, if I am using COS5 with LTFT disabled (B3801), B4205 maxed out, actively using my MAF and trying to use B3647 to command my AFR what type of tune is it called? Is that semi-open loop? Or is it just half-ass?

B3618 is still affecting my AFR. I thought that PE should be disabled by the way I have my tune set up.

Since my VE is set up pretty well, should I be looking to go MAFLESS??

Current tune attached.

Open Loop (OL) with MAF = OLMAF

There are 4 possible combinations:
- OLSD
- OLMAF
- CLSD
- CLMAF

Semi-Open Loop (SOL) is where B3647 contains cells that command stoichiometric AFR (i.e. EQ 1.00)... whenever the PCM goes into OL those cells EQ 1.00 cells cause the PCM to use STFT's to trim to EQ 1.00... this is called SOL.

Note that OL is present in the following situations:
- always in OLSD and OLMAF;
- at WOT and/or when cold in CLSD and CLMAF.

Thanks for the explanation. That is helpful.

The reason I ask is dialing in AFR is still a bit tricky. Seems that the most responsive change was to update the MAF calibration. Now it seems difficult to use B3647, A0008 and B3618 to wok together.

I guess the question I am trying to ask is: Is there a better or easier way?

I finally understand most of the basics but wonder if I will ever get "done".

Anyway, enough crying.

Thank you for all of your help. I really appreciate it.

Bob