Help with VAG-COM figures please...

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I've done some logging with VAG-COM and I was wondering if anyone had any advice?

My problem is that the engine has gotten really sluggish at idle, when running, and when pushed over the last week.

I did the same logging as this thread here http://www.audi-sport.net/vb/showth...understanding-my-VCDS-ignition-timing-figures

All the logs are from 4th gear runs from 1000RPM up to the redline.

When pushed it seems to take a little longer for the turbo to kick in and you can feel it pulling back at 3000ish RPMs, which seems to be backed up by some of my logging figures.

I seem to be having a lot of problems with block 020. I've a 1999 S3 APY with a Custom Code stage one remap.

When the guys were putting on the remap they said they had to pull back the timing a bit as the ECU was pulling back to standard boost at high revs. They said this was because oil is getting past my turbo and into the mix, and that when I sort out the problem with the oil, that I would be able to add some more timing using Custom Settings software.

I've included a pic of the values read from the ECU by Custom Settings.

Any advice greatly appreciated!


Blocks 020, 031, 115 (two runs for good measure!)





Blocks 020, 115, 118 (two runs for good measure!)





Blocks 002, 115, 120 (just to check MAF, values seem OK for a stage one remap???)



Custom Settings Values Read from ECU


 
there's some margin for dialing some of the removed timing back in.. as a guide to a max of 6cf
replace the turbo if thats the oil mist source as they are right its reducing the effective octane of your fuel hence timing needs pulling back

-6 degrees is what they have done yes via custom settings
 
-6 degrees is what they have done yes via custom settings

Thanks Bill. What does "CF" stand for?

Do you have any info on the following...

If I used Custom Settings to read the values from my ECU before getting a remap would "Ignition Timing Additive Offset" be set to zero?

If the timing didn't need to be pulled back when I got the map put on, then what value would "Ignition Timing Additive Offset" bet set to? i.e. what's the default value for this channel for a Custom Code Stage 1 map?

Do all the other values that I have read from the ECU look standard for a Custom Code Stage 1 map? So, what I'm wondering is, is the only modification made to the map to the timing.
 
Thanks Bill. What does "CF" stand for?

Do you have any info on the following...

If I used Custom Settings to read the values from my ECU before getting a remap would "Ignition Timing Additive Offset" be set to zero?

If the timing didn't need to be pulled back when I got the map put on, then what value would "Ignition Timing Additive Offset" bet set to? i.e. what's the default value for this channel for a Custom Code Stage 1 map?

Do all the other values that I have read from the ECU look standard for a Custom Code Stage 1 map? So, what I'm wondering is, is the only modification made to the map to the timing.

CF is correction factor, aka how much timing is being puilled out due to knock
The default value is Zero in unisettings/custom-settings

CC map or others do not typically use these at all.
Only used to tweak and adjust after mods typically. stage 1 reflash is just reflash.. yours has oil issues as you describe which is why they pulled their stock stage 1 ttiming back out until you could fix it.. as oil going thru your intake is reducing your effective octane hence it pinking and pulling timing via knock sensors.

these are adaption channels.
your only adjustment was to ign timing, retarding it 6 degree's
 
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Perfect. That makes sense now. So when I sort out the oil issue I should be able to bring the "Ignition Timing Additive Offset" down to zero, and that will leave me with a standard Custom Code Stage 1 map.

I'll obviously not just whack it down to zero in one jump. Probably go one degree at a time and test block 020 to make sure the timing hasn't gone mad. Sound like a good plan?

In a car that doesn't have any issues, would you expect block 020 to show all zeros all the way up through the rev range? So I guess what I am asking is - what is the "normal" output from block 020 from a car that doesn't have any issues?
 
My brothers completely stock S4 was showing CF values similar to yours, albeit when running 95 octane fuel. I cant remember if we tested it again with super unleaded though.
 
I would personally use a guide of seeing 3 to 6 CF's, no more.

Octane is a related item to timing... lower octane fuel, expect some pull

VPower gets my vote
 
My brothers completely stock S4 was showing CF values similar to yours, albeit when running 95 octane fuel. I cant remember if we tested it again with super unleaded though.

I use Maxol E5 petrol (http://www.maxol.ie/general-content/e5-questions-answers.html). They claim it's 99 octane...so hopefully I should be OK there!


I would personally use a guide of seeing 3 to 6 CF's, no more.

Octane is a related item to timing... lower octane fuel, expect some pull

VPower gets my vote

Based on a range of 3-6 CF then my block 020 figures are fine?

So what would explain my boost dropping off between 3k - 4k revs? On one of the runs it drops down at near 3k and doesn't come back up to the same level until 5k revs. There doesn't seem to be a correlation between the CF on 020 and my boost falling off.
 
First of all start with the obvious stuff... vacuum leaks and boost leaks. Be surprised where the little buggers come from, I have had nothing but probs with mine while on my build... .chasing my tail all over the place with split pipes etc... Essentially anything hanging off the inlet mani is a good place to start... all the PCV pipes etc VAG fit will go over time. I insoected mine when I put my engine back together and they looked fine... couple of months down the line and they were shot... I had wobbly performance for ages thinking it was just because I hadn't finished the mapping and it was a couple of cheap *** split pipes!!!

Check the tighteness of the charge pipe clips where they join... these get tired and loose over time, OEM hoses will shrink and go hard etc... to do the job properly its bumper off to get at the SMICs but its not a difficult job and worth while for peace of mind...

<tuffty/>
 
First of all start with the obvious stuff... vacuum leaks and boost leaks. Be surprised where the little buggers come from, I have had nothing but probs with mine while on my build... .chasing my tail all over the place with split pipes etc... Essentially anything hanging off the inlet mani is a good place to start... all the PCV pipes etc VAG fit will go over time. I insoected mine when I put my engine back together and they looked fine... couple of months down the line and they were shot... I had wobbly performance for ages thinking it was just because I hadn't finished the mapping and it was a couple of cheap *** split pipes!!!

Check the tighteness of the charge pipe clips where they join... these get tired and loose over time, OEM hoses will shrink and go hard etc... to do the job properly its bumper off to get at the SMICs but its not a difficult job and worth while for peace of mind...

<tuffty/>

Thanks. I will follow up on that as well as logging block 32. I'm going to get it checked

The engine doesn't even sound\feel good at idle and off boost.

At idle it has gone a little more erratic, it usually ticked along nicely at idle and sounded quite smooth, but now the timing seems to be out on it, and it doesn't sound as smooth as it used to, more rattlely, if that makes sense.

Off boost it just feels a bit dead and lacks the nippy response it used to have.

Another noticeable thing is when you lift off the gas, instead of the car rolling along smoothly, you get a feel of some resistance dragging it back. It was the kind of feeling I had when my MAF was dodgy - which is why I logged the MAF values, but they seem fine. You notice it too when lifting of the gas in 1st gear, instead of it decelerating smoothly, it's just real cludgy and jerky.

So the fact that it doesn't feel good off boost and at idle, that must mean that I've something else going on, other than my turbo? Although I did read somewhere that split hoses can cause problems off boost too.

What do you think?
 
Just to note. In the last 6 months I've replaced the following - MAF, All Ignition Coils, Spark Plugs. And about a year ago I replaced the CTS.

Looking at http://www.elitedubs.com/index.php?topic=988 it has the common problems for rough idle as - Rough Running At Idle - MAF, Ignition Coil, Spark Plug, VAC Leak, O2 Sensor, TB, CTS

So that just leaves me with VAC Leak, 02 Sensor, TB, ...

I also got the TB cleaned a few months ago, although my Turbo is leaking oil so this could have it filthy again with oil maybe?
 
The values from block 032 are:

idle value = 1.9%
part throttle value = -1.6%

Do these seem OK?