Help with first set of tests please - DATA now added

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Imola

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Hi

With regard to my ongoing issue I posted here, I have purchased a Ross Tech licence for VCDS-Lite and it finally arrived today (annoyingly it took too long to arrive and I was off work yesterday and Monday hoping to use it!!+)

Now I have it, when I get home tonight, how should I use it to check my MAF values, N75, boost etc.? Do i leave the car stationary and log? Do I run it on the road? Do I need to boot it in a gear form x revs to y revs?

I also am starting to think my DV is problematic - is there any way to identify this from the logs?


Any help much appreciated as this is my first time with anything like this

thanks
 
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thought i might have a bit better response :)
 
try the vcds forum on the site, hope u get some help soon
mark
 
Assuming you haven't read this thread then...
http://www.audi-sport.net/vb/a3-s3-...-help-please-read-before-posting-updated.html

Info on blocks and what they mean can be obtained in the thread for further reading... also includes an brief explanation of how to do a log run

Without know hat you think the issue is its difficult to advise what blocks are best to log first...

Always start with a fault code scan...

Why do you think your DV is problematic? they pretty much do one job...

A list of fault codes (which again can be looked up using links to Ross Techs wiki in the thread above) would be a start and an explanation of what symptoms you are experiencing

<tuffty/>
 
Thanks Tuffty

The DV didn't hold pressure very well when I covered the vac hole after pushing up the piston - it turns out it is a fake Chinese rip off of a Forge, sold to me as a Forge 7 years ago :(

The car surges on gentle throttle openings in 3rd 4th around 3000-4000 - it also lags for a couple of seconds when I open the throttle on the motorway at normal speeds whereas it used to just pick up and go almost immediately

I am also trying to establish the cause of my low end torque loss. I have a new VAG supplied MAF that reads 3-4g/s on tickover and 50 or so g/s max flow on vcds. I think I should be seeing more like 200+ g/s on a tuned S3?
 
Imola said:
Thanks Tuffty

The DV didn't hold pressure very well when I covered the vac hole after pushing up the piston - it turns out it is a fake Chinese rip off of a Forge, sold to me as a Forge 7 years ago :(

The car surges on gentle throttle openings in 3rd 4th around 3000-4000 - it also lags for a couple of seconds when I open the throttle on the motorway at normal speeds whereas it used to just pick up and go almost immediately

I am also trying to establish the cause of my low end torque loss. I have a new VAG supplied MAF that reads 3-4g/s on tickover and 50 or so g/s max flow on vcds. I think I should be seeing more like 200+ g/s on a tuned S3?
Click to expand...

When you say max flow, are you actually talking the car out and giving it the beans to log MAF values? You're right though it should be near 200g.

I had the same thing on my car when I first brought it - turned out to be a faulty N75 (less than 40 off eBay for genuine one) also replaced the DV for genuine one and been perfect ever since. Definitely worth doing imo...

Don't bother replacing DV with forge.. Stock one works perfectly :)

Any fault codes?
 
Thanks Russ - I have been hesitating over N75 as unsure what it would do. Will be ordering today (I already have the £40 in my watch list :)
 
Hi all

Could you look at the following and comment on my ongoing issues please - the problems are well documented in other threads.

This test was a run from stationary to 100mph flooring it in each gear as I wasn't sure what would be the best test. The MAF appears low to me

9680136594_11f5fae945_b.jpg
 
Dude... did you read the stuff in the link I gave you?

Run should be done in third gear, start at 2000rpm and accelerate foot to the floor until redline or as close to redline as is legal and safe...

You say your issues are documented else where but with out this info in this thread there is no context... no one is going to hunt around and look for your threads dude... post the issues here and we can go from there...

Bin the chinese DV... it leaks... Forge ones leak so this will be worse... bang an OE DV on, clear the fault codes and report back on any that come back... if you know something is not working then replace it... all you are doing is skewing the results of any diagnosis...

What year/engine code S3 do you have? makes a difference to suggesting blocks to check... as does knowing what you think the symptoms are

<tuffty/>
 
Sorry Tuffty, the run was last night around 5.00pm, before i saw your post and link :(

Will do the run as you suggested this evening after work :)

The car was registered 1st Jan 2003 and is a BAM


Sorry about not putting the details in - I thought people might not like me reiterating the same info.

Problem was as follows:
There has been a nice torque spike around 2500 since AMD chipped 7 years ago. This had gone.

It also sort of hesitated/jerked/surged (hard to explain) between 3000-4000 when accelerating on a partial throttle when joining a motorway etc..

Disconnecting the MAF made it much more like before as far as the torque spike was concerned, and helped smooth that surge/hesitation thing too.
So, we replaced the MAF with a new VAG unit. It didn't cure it, but it feels better most of the time.


Now, when I am sitting on motorway at, say 70 (with new MAF on), and decide to 'squirt' it by the car in front, I need to press the pedal much further (like on a normally aspirated car) and there is often a big lag before it goes. It used to require the smallest of presses on the pedal and shot off.


To explain the torque spike I refer to. After reamp, +DV, + Milltek the car pulled hard at 2500rpm easily leaving traffic behind (very flat delivery until 3500 before the remap etc.). Around 3500ish it then pulled really hard and 4500ish it was warp speed until near the red line.
 
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Okies...

Bin the DV and fit an OE valve...

Clear fault codes and run the car awhile to let stuff settle then rescan and post any that return... do not clear the codes... with the engine warmed and idling, check block 032 and see what fuel trims are doing...

Log block 003, 020, 118 initially as directed... engine needs to be at operating temp...

Only post the run data... (remove all the chaff around it but leave the headings obviously... )

<tuffty/>
 
Hi

Ran the tests tonight. Seemed to go well, but lacked the torque at 2500. Still has old DV on though as I ordered a new Forge when we realised mine was a fake and still waiting for the genuine Forge (didn't realise they were not as good as oem :( ).

Couple of runs - block 020 only gave me four boxes with 0 in and CF at the top, so not included here

Run 1

9679176357_baee02172e_o.jpg



Run 2

9679176265_6fd4c7eeaf_o.jpg




Block 32 at tickover before the test runs

9679176241_8c05c10fa5_o.jpg


Block 32 at tickover after the test runs

9682413516_c5710ebde4_o.jpg
 
Adding fuel on idle... looks like you have a vacuum leak and the n75 looks flat out... IAT's look high (guessing you are on std SMIC's)..

Plus side, 0 CF's means no timing pull...

Now try blocks 002, 031 and 115...

<tuffty/>
 
Forgot to say - no fault codes at the minute

Standard intercoolers
 
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Hi

This is this morning's run - still has Chinese DV. Much cooler this morning with light rain, so it felt stronger and more like before - not as it was though

9685904954_8588120bfa_o.jpg
 
Hummm... looks like your turbo is tired or you have a leak somewhere... actual boost is struggling to meet request and based on your 118 log previously the N75 is flat out..

Smoke test next... (and change the DV)

<tuffty/>
 
Hi Tufty

Not had a chance to find a place to get a smoke test yet, but the car was very much better after fitting the new DV and checking all the pipe clamps (replaced some that didn't seem really secured). Nice torque surge again and increased power.

I had also ordered a replacement N75 and that was the icing on the cake :) Suddenly the car stopped hesitating around 3000-4000 and instead simply takes off at 3500 like it did 7 years ago (but probably even more strongly now) when first chipped. I think over time it has probably been slowly losing that sudden urge and as it was a slow decline (and the car was still fast), i didn't notice it until it came back. Feels like a motorbike powerband now :)

Thanks for the help, i literally could not have done this without the forums help
 
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MAF is now 208g/s which with the /0.8 calc works out around 260bhp

I think this sounds reasonable for a stage 1 tune with milltek and Forge that's done 97,000 miles now (77,000 of them chipped and milltek :) ) All else standard on engine side

I would like it nearer 300hp of course..............
 
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