NefMoto

Noob Zone => Noob Questions => Topic started by: TLS on April 21, 2015, 02:34:51 AM



Title: VCDS Unreg - Fuel Trims
Post by: TLS on April 21, 2015, 02:34:51 AM
Hi
I have VCDS Lite but have not registered it. I want to check my STFT and LTFTs.
I added fra_w and rkat_w to my logging and gave it a go.
fra_w logged at 0.99997 and rkat_w at 0 for the log.
Am I doing something wrong or do I just not understand what I am reading.

I have an intermittent rough idle that I am trying to chase. The RossTech wiki suggests a trim on the STFT will indicate a vac leak and affect idle and not at LTFT. Is that what I am seeing?

1.8T


Title: Re: VCDS Unreg - Fuel Trims
Post by: aef on April 21, 2015, 03:56:45 AM
measurement block 032 is your trims


Title: Re: VCDS Unreg - Fuel Trims
Post by: TLS on April 21, 2015, 04:00:04 AM
Does not work on unregistered vcds, unless I'm not doing it right.


Title: Re: VCDS Unreg - Fuel Trims
Post by: TLS on April 22, 2015, 01:38:10 AM
OK so I upgraded to Lite-registered.
Did a TBA.
Checked 032
Looks ok.
Still not happy with idle smoothness.


Title: Re: VCDS Unreg - Fuel Trims
Post by: nyet on April 22, 2015, 09:46:12 AM
Log misfires yet?


Title: Re: VCDS Unreg - Fuel Trims
Post by: TLS on April 22, 2015, 06:41:30 PM
I have never seen a number in my CountMisfireCyl columns.
You saw in my last logs I was getting CFs with boost/revs.

I'll have to log it again.
When I just installed the new DV my rkat_w was -8.9 but now is negligible.
Also my fra_w 1.09 and is now 0.9.

My CFs maxed at -6   -9.75   -6   -6.75 with Air intake temp at 47degC, boost 1430mb, tabgm 790degC, lambsg .898.


Title: Re: VCDS Unreg - Fuel Trims
Post by: spacey3 on April 23, 2015, 01:32:57 AM
I have an intermittent rough idle (1.8t though), all fuel trims, CF's, coil packs, etc. are all good.

However it shows up as misfires (def. worth checking as people have said), I put it down to in part being due to using colder spark plugs, although it could be an iffy injector I guess.


Title: Re: VCDS Unreg - Fuel Trims
Post by: TLS on April 28, 2015, 01:34:02 AM
More testing required.
They were zero because I just cleared DTC for intermittent engine start denial by immobilizer...


Title: Re: VCDS Unreg - Fuel Trims
Post by: TLS on April 28, 2015, 02:31:50 PM
How long do I have to drive to get LTFTs to set?

I did about 15km this morning and the 032 1 (LTFT Additive - Idle?) is -6.2 and the 032 2 (LTFT Multiplicative - partial?) is -0.8.

The STFT was mostly +21 - +25 during this run, so I thought that would pull the LTFT back a smidge toward 0.

RossTech suggests -ve at idle may mean blocked air filter.

Am I getting it right now?


Title: Re: VCDS Unreg - Fuel Trims
Post by: hammersword on April 28, 2015, 04:11:17 PM
please check also block 093 for camshaft phase position! This should be 0, if not there should be a problem!
Acceptable is +/-3deg... Going to minus (-) means rough idle


Title: Re: VCDS Unreg - Fuel Trims
Post by: TLS on April 28, 2015, 08:52:50 PM
I don't have those blocks. Only 09x series I have is 099.


Title: Re: VCDS Unreg - Fuel Trims
Post by: TLS on April 30, 2015, 04:55:25 AM
I removed TB, cleaned it and the IAT sensor and re-fitted.
Removed Air Filter, replaced with new.
Removed ICM and cleaned the surface, added fresh thermal couplant and re-fitted.
Removed #1 plug and checked. BKR6EK. Has dual electrodes on the side with curved tips so you can't really check the gap. Little coating but not too bad. Will order new ones anyway. Probably done 15k km.
I then reset the codes (none) and did TBA. Finished OK.
Then went for a 10km drive. So far slightly better idle, very small idle and partial trims.
Good start.

Now I gotta fix these CFs.