Lets talk tuning (KiDo Tunes)

[bigBADbenny]

The link is simply that a lot of Matt-tuned cars are logged, Matt spotted the issue (with my car at least) as causing problems with his tunes, and I (and others) drew a conclusion that aggressive AVCS maps may exacerbate a pre-existing AVCS out of sync issue.
Matts tune is not the only tune that has different AVCS maps.
As part of my diagnosis it was suggested I change tunes.
Doing that helped a little in general driving, but not cruise. Best bet is to replace AVCS parts, but Matt is working another angle that may be relevant.

Could we please limit discussion of the AVCS issue to a thread I've dedicated to it? viewtopic.php?f=18&t=20233
Everything we know is in the first post, pending updates.

[XT_for_me]

Brendon, I think you will find that many tuners do not bother with the AVCS at all, and of those that do change the settings many would not do comprehensive logging of the AVCS timing so would not notice the irregularities. These are most easily diagnosed by comparing the left and right AVCS timing in a log file and when there are notable differences it is an indication of a problem. The oil filters on the AVCS are known to clog easily and many mechanics remove them during a service but I don't believe that is a good approach. They were fitted for a reason and should be left in place after cleaning.

[<GB>]

Brendon, I think you will find that many tuners do not bother with the AVCS at all, and of those that do change the settings many would not do comprehensive logging of the AVCS timing so would not notice the irregularities. These are most easily diagnosed by comparing the left and right AVCS timing in a log file and when there are notable differences it is an indication of a problem. The oil filters on the AVCS are known to clog easily and many mechanics remove them during a service but I don't believe that is a good approach. They were fitted for a reason and should be left in place after cleaning.

its brandon btw,

all the tuners ive used do tune avcs in non cruise most may not play with the cruise avcs this might be why this issues are happening as you know most cars are not all running in open loop for long, maybe the changes that are happening in the cruise are too agressive and causing the issue? do you not think this is plausable?


im aware how they check these i checked mine on the weekend and its fine.

[coyote]

I have diagnosed this exact issue on numerous standard cars over the past 6 months.

It is not tune related.

[Rome_BRZ]

I have diagnosed this exact issue on numerous standard cars over the past 6 months.

It is not tune related.

Thanks for sharing this Tony.

[XT_for_me]

Brendon, I think you will find that many tuners do not bother with the AVCS at all, and of those that do change the settings many would not do comprehensive logging of the AVCS timing so would not notice the irregularities. These are most easily diagnosed by comparing the left and right AVCS timing in a log file and when there are notable differences it is an indication of a problem. The oil filters on the AVCS are known to clog easily and many mechanics remove them during a service but I don't believe that is a good approach. They were fitted for a reason and should be left in place after cleaning.

its brandon btw,

all the tuners ive used do tune avcs in non cruise most may not play with the cruise avcs this might be why this issues are happening as you know most cars are not all running in open loop for long, maybe the changes that are happening in the cruise are too agressive and causing the issue? do you not think this is plausable?


im aware how they check these i checked mine on the weekend and its fine.

Sorry Brandon, I didn't mean to get your name wrong. As Coyote says, it's not tune related. However getting a performance tune may bring the problem to the fore where the OEM tune is more tolerant of the issue.

[<GB>]

thats ok!

well ive heard other tuners think differently so each to there own, maybe the high km cars shouldnt have much avcs tuning as it causes them to fail faster.

[KiDo_Tuning]

Benny so that is 2 auto 07's that have confirmed their avcs system is fine, every other manual car that has bothered to log it and post results so far has the issue?

My manual 07 doesn't have the issue, as checked by Bruce.

how many km? who tuned it?

seems lots of these avcs issues are happening to matt tuned cars...

Two dead stock cars confirmed
One Pulse tuned
One HPF tuned
5 EcuTek tuned(2 Bris, 3 Syd waiting for me to remove EcuTek)
Two Roger Clarke tuned(UK)

Common denominator... all 07/08 2.5L Turbo
Yet to see any 03~05 FXT or any WRX with the issue

There is a distinct sine wave pattern the the signal on the RH side bank that has hinted at the cause which I am checking with an oscilloscope this weekend

[bigBADbenny]

Thanks for your help with diagnosing the issues.
Wear and tear/oil are obviously major contributing factors.
But the real breakthrough could be getting the cause of the oscillation worked out.

[KiDo_Tuning]

Thanks for your help with diagnosing the issues.
Wear and tear/oil are obviously major contributing factors.
But the real breakthrough could be getting the cause of the oscillation worked out.

Thanks for the patience mate, it can only benefit the community as a whole if a fix can be identified!

Have one owner testing a solution... electrical engineer with 4 diodes

[<GB>]

Two dead stock cars confirmed
One Pulse tuned
One HPF tuned
5 EcuTek tuned(2 Bris, 3 Syd waiting for me to remove EcuTek)
Two Roger Clarke tuned(UK)

Common denominator... all 07/08 2.5L Turbo
Yet to see any 03~05 FXT or any WRX with the issue

There is a distinct sine wave pattern the the signal on the RH side bank that has hinted at the cause which I am checking with an oscilloscope this weekend

well there are a few of your cars kicking around with issues... anyway may be they shouldnt have avcs tuned at all? as i said could tuning avcs in the cruise mode be making them fail premuture ? high km cars having issues, should they not have avcs played with?

[bigBADbenny]

There is no proof of that, either way.
I've been polling opinion and opinions are split on the matter.
I agree with you, but it's not black and white, especially since the system is somewhat prone to issues anyway regardless of mapping.

[<GB>]

There is no proof of that, either way.
I've been polling opinion and opinions are split on the matter.
I agree with you, but it's not black and white, especially since the system is somewhat prone to issues anyway regardless of mapping.

i know its not black and white but with an expensive repair is it worth it?

[bigBADbenny]

I want to see Bruces cruise log

[KiDo_Tuning]

Two dead stock cars confirmed
One Pulse tuned
One HPF tuned
5 EcuTek tuned(2 Bris, 3 Syd waiting for me to remove EcuTek)
Two Roger Clarke tuned(UK)

Common denominator... all 07/08 2.5L Turbo
Yet to see any 03~05 FXT or any WRX with the issue

There is a distinct sine wave pattern the the signal on the RH side bank that has hinted at the cause which I am checking with an oscilloscope this weekend

well there are a few of your cars kicking around with issues... anyway may be they shouldnt have avcs tuned at all? as i said could tuning avcs in the cruise mode be making them fail premuture ? high km cars having issues, should they not have avcs played with?

Most people ignore it, as in the case of the Pulse tuned car. Thought it was normal for a tuned car. Coyote has clearly said he has seen it as well

Another UK workshop I work with is confirming their logs for the sine wave pattern generated but they noticed it too. The US guys have had the problem too. Coincidence?

The sine wave is consistent, if it was oil pressure or even dirty solenoids... the wave would not be so consistent!