NefMoto

HI there ,

I am in need of some assistance .. I simply can not get the EGT's down on my 20vt , I have edited LAMFA and BTS ect to sort out fueling . No joy. It gets a bit bette rif I run WMI , but not the best. The ECU still requests 0.63 AFR from 4500 rpm.

I have attached logs

Harware
AGU 20VT
S3 pistons , S3 rods
S3 ECU
S3 maf
s3 Map
S3 injectors in the AGU manifold. I modded the manifold so that the inectors sit as deep as possible
S3 KO4-23 turbo + manifold
S3 EGT sensor
ADR normally aspirated 20V camshafts
VVt system
SAI delete in file
N80 & N112 deleted in file

Thus far i replaced with new parts :
MAF
Lambda (WB)
EGT sensor
Down Pipe
Silencer - exhaust has a single silencer

I have a BASIC tuned file that I made up myself .. I think I have covered the basics

All of the above resides in a mk1 golf.

Your comments are welcome .

Thanks

Two things.

1. Measure exhaust backpressure (no idea what exhaust you have on there).
2. Swap cams to stock and time them correctly, and see if it's better.

Usually high EGT's are either due to high backpressure or incorrect camshaft setup.

High PRJ ,

Thanks for the swift reply.

I just fitted the new exhaust , since this is a hobbt car , I didnt have to fit many silencers ... I believe its pretty free flowing . how do you measure the exhaust back pressure and where about ?

The cams are timed correct , however I suspect that due to the fact that its NA cams , its causign an issue ..

The exhaust backpressure you can measure in two places.
One place is after the turbo, using this, you will measure how restrictive your actual exhaust and downpipe is.
The other place is before the turbo, this will measure how restrictive your turbo's hotside is.
I think you can just do a quick test for the exhaust, to make sure it's not restricting anything. There should be barely any pressure post-turbo if the exhaust flows well.

But looking at the logs, I can see a few things wrong.
A good K04 on an Audi S3 can make 1200mbar boost at 6000 rpm. Your turbo is making 900mbar, with N75 at 95%.
Also, your timing values in mid range are a bit low, but at top end they are quite advanced, but you have absolutely no knock.
This would indicate that you have some sort of issues with the dynamic compression ratio. So it could be an issue with the camshafts, as actual cylinder filling is quite low.
I have not looked at the parameters of the ADR cams, but if they have overlap, then it's not a good thing for a turbo engine with a little K04 on it, and it can cause this problem.

Hi Prj ,

I will revert to a set of S3 cams to rule this out .

You mention 1200 mbar @ 6000 rpm , I assume you took sea level into consideration ? I am not at sea level , for me atmospheric pressure is 820 mbar ... So , it works out to 1120 mbar at 6000 rpm for me.

Timing is pretty much stock , I have not fiddled with that as yet.

I also pondered why I get no knock at all. Your theory makes sense .

Will give it a bash and post back.

thanks

What knock sensors you running? Original agu? And what Ecu are you running?

Hi Littco ,

BAM / AMK knock sensors mounted in place of the AGU sensors . Cleaned and torqued to 20nm

ECU is the S3 , BQ part number.

hi ,

Question : The logs show 4 th gear pull's , yet I used 3rd gear. Could this be the issue ?

I am using a 02J gear box from audi a3 1.8T , the S3 ECU uses a 6 speed .

Ok,

More questions sorry..

Did you swap the camsensor wheel?

I've not long had a similar setup in my TT, which had high EGTs at the start.

The Cambelt was 1 tooth out although I had no error code.. I fix the Cambelt but then got a camshaft to crank timing error but my EGTs went down by 200degrees straight away, swap the agu camsensor wheel for an ARY one, same as Bam and problem solved.

The camsensor wheels on agu and bam are different and not compatible.

Littco ,

Greetings,

wow .. I always assumed they were the same (AGU and BAM)

I spoke to the parts guy at Audi

AGU cam postion sensor - 058 905 161B - same across the range (BAM/AMK/APY ect)
Impulse wheel - 06B905234A - again same for all the engines.

I dont doubt your experience. I have seen a few 1.8T's that dont throw a code when the timing is out by a tooth or less. I did check the timing ,perhaps its wrong ...

I do have a new BAM sensor and impulse wheel  , wont hurt to try this out

Edit : Scouring the net shows that 06A906018 came with a 1 window setup , and later versions with 4 window ..

Hopes are high !

Interesting, as its quite well documented that it needs to be changed on the audi forums. I'll get some pictures if I can but they are different physically when you look at them , if I remember 1 has 3 windows and the other 4.

I know plenty if people running N/a inlet cams on their setups without issue, admittedly only the inlet so couldn't comment on what would happen if the exhaust was run.

Also might be worth checking the cam chain setup as I assume you removed the chain when you fitted Vvt?

Littco ,

I understand that the chains are the same between vvt and non vvt - Yes , I removed the entire setup and re-installed it .

I will definately have a look a the both the sensor and impulse wheel a little later on .

Thanks for the help

Chains are the same just need to make sure you have the correct 16links between timing markings, sorry if you know this, just checking.

No problems . Thanks for the reminder ..

Yeah , I know its 16 links between the sprocket .. but it some how doesnt seem that simple to me ..lol

I will first try , then cry !

Hi Littco ,

Some feedback . The AGU head had the 4 window trigger already. I believe the AGU comes with the 4 window trigger - possible that AEB comes with a single window trigger.

When we speak of windows , we mean the cut aways on the impulse wheel , correct ? I took the entire unit off the bam head an placed it alongside the AGU . Identical..

Now where to ...

Tensioner not doing its job ? Surely that will throw a code ??

Ok... Mine were Definately different between agu and bam. So no ideas there.

Can only suggest timing then. Assume you've put a stock map back onto elongate any map issues?

Hi ,

As i said , i dotn doubt your findings .. just puzzled with my findings ...

Yes , with the stock map , its pretty much the same . I even got the EGT limit exceeded code in one instance

I'm going to say cam timings out then.

Not had a look at the logs but what's the requested v actual lambda? And what timing you running when its going rich?

No, this just means you will have to re-tune gear detection later.

From 2000 rpm till 4500 rpm or so , its fine , 0.82 req vs 0.81 ~ 0.82 , after 4500 rpm , egt's start climbing and it then starts to go down to 0.63 req , 0.75 actual. I have read up that 0.75 is the richest the ecu will register - the reason why my lm2 is spot on to the ecu requested.

Timing is as follows
3000 rpm  , 4.5 deg
3500 rpm , 3 deg
4000 rpm , 7.5 deg
4500 rpm , 13 deg

Red line its at 22-24 deg

Thanks PRJ , least of my problems now ... I will look into this at the end of the project

Check physical cam timing, your timing is out I think.

I did , I also took it to an audi tech , he commented its all good , a few dollars later ..

Ok , so I will look into it again .

Know of any resource that documents this fairly well ? The setup proceudre ? I will you tube it and google as well .

Also , no fault codes related to crank angle and cam position.

There's a mark on the crank pulley and one on the engine block, these should align along with the mark on the cam pulley and cam cover.

What are your egt temps as per the log at 4500rpm? That's incredible low and by co-incidence about the point cdnws ( cam switch takes place) might be worth setting cdnws to 0 to lock the cam and stop switching and see if that helps.

Hi ,

850 at 4500 rpm , 875 @ 4750 rpm

Yes , I recall those cam/crank timing  marks . I will re look at this shortly.

So lock the camshafts as a test ? Its seems to me that the egt's are high from the onset. From 2000 rpm , the egt is already close to 700 deg c

Is it not low since I didnt really ad timing to the stock maps ? Or should the ecu advance till it gets to the optimum timing ? Do you change both the basic and optimum timing maps ?

Hi ,

I checked the crank to cam timing.

I lined up the marks on the valve cover and exh cam pulley. At this point the crank pulley was approx 2-3mm(to the rear of the engine) away from the mark on the block. I take it tis was retarded in relation to the cams . Redid the belt tension and it seems good now .

Lets see how it goes.