VAG COM Results Help Needed - Where have all my horses gone :( !?!

[metricspaces]

I've finally gotten around to doing some logging with my VAGCOM. The results look crap! Apperently I'm only getting a max of 163.5 hp at 5080 RPM and 183 lbft at 2720 RPM!

I'd appreciate any advice on where I should start to try and get this sorted. New MAF? What else?



I've a 1999 Audi S3 APY. It seems quite slow for something that's meant to have 210bhp. There's no fault codes showing up in VAGCOM. I've just had it serviced, the throttle body cleaned\realigned. MAF checked.

So I've followed the guide mentioned http://www.audi-sport.net/vb/showthread.php?t=67011 for logging. I stuck the car in 4th gear and took from 1000 RPM up to the red line.

I did two runs logging 002, 115, 120. I used the data from 120 to create my graph. Here's the data and graphs from my first run (ignore the 001 - i meant to log 115!). Max of 162 hp at 5640 RPM and 172 lbft at 2640 RPM.

Here's the data and graphs from my second run (i logged 115 correctly here!). Max of 163.5 hp at 5080 RPM and 183.2 lbft at 2720 RPM.

 

[IIIadidasboy]

You should be logging group 005, and don't forget to do the coasting with it either out of gear or your foot on the clutch.

Check this thread from one of the guys from Ross Tech:

http://forums.audiworld.com/showthread.php?t=2580766

Or alternatively, do a search for "Butt Dyno" on Google

 

[MintyS3]

The MAF readings are very low so could be the maf sensor is broken.

 

[metricspaces]

The MAF readings are very low so could be the maf sensor is broken.

Yep, the readings seem extremely low compared to the values other people have gotten on here with VAGCOM.

But how do you actually determine the the MAF sensor is broken?

Is solving a problem like this going to be by process of elimination? Replace MAF, do readings, replace something else, do readings etc...until I get the correct readings?

 

[badger5]

as said MAF is you problem..
180g/s expected for 210/225 motor (std)

200+ when mapped

common.
IPA clean it or better just fit new one and relog

 

[metricspaces]

Thanks, I'm going to get a new MAF ordered and relog. Is there any other obvious things that could be causing such a lack of performance?

 

[MintyS3]

Your not seeing any faults so imagine its just the maf. I would go with that first.

 

[metricspaces]

Well, every now and again the fault below pops up, but I clear it and it doesn't come back for a long while.

It was there before I did my runs for the VAGCOM logs. I cleared it before the runs. It wasn't there after the runs.


1 Fault Found:
16795 - Secondary Air Injection System: Incorrect Flow Detected
P0411 - 35-10 - - - Intermittent

 

[IIIadidasboy]

Have a look here for an explanation of the fault:

http://wiki.ross-tech.com/index.php...Air_Injection_System:_Incorrect_Flow_Detected

 

[metricspaces]

Yeah I mentioned this to my mechanic before. Said he has seen this as an intermittent problem on a lot of VAG's. He told a look over the pipes and couldn't find any leaks...so what to do?

I don't think this is causing my problems with the power, because the fault would have shown up after my runs for VAGCOM logging.

 

[IIIadidasboy]

See what happens after you change the MAF. Are you doing it as an exchange - normally Audi will do this for approx. £80

Finding boost leaks can be a PITA, I recently came across info on how to do a DIY boost pressure leak test - but now I want it I can't find it!! I may have saved it, or a link to it, on my work PC, I'll check tomorrow.

 

[metricspaces]

I'll probably do it as an exchange. But am I correct in understanding that an exchange part is just a reconditioned part?

I've heard of people changing the MAF only to get another dodgy one. If the exchange part is just a refurbished part, am I better of going for a brand new one?

Is it possible for the MAF to be tested to see whether it's faulty, other than doing what I did above and logging the values?

 

[badger5]

get the new one and relog..
simple as

if its working correctly it will read higher and the car will feel faster

 

[Dani_B19]

See what happens after you change the MAF. Are you doing it as an exchange - normally Audi will do this for approx. £80

Finding boost leaks can be a PITA, I recently came across info on how to do a DIY boost pressure leak test - but now I want it I can't find it!! I may have saved it, or a link to it, on my work PC, I'll check tomorrow.

You found it yet mate? Would love to pressure test my set up.

 

[metricspaces]

get the new one and relog..
simple as

if its working correctly it will read higher and the car will feel faster

Yep, that is what I'm going to do. Just wondering about the new MAF sensor that gets put in. If the garage say that the part is on exchange - is this a refurbished part? Are you saying that I shouldn't get this and instead ask for a brand new one i.e. not on exchange? Thanks.

 

[IIIadidasboy]

You found it yet mate? Would love to pressure test my set up.

Yep, found it at last:

http://forums.vwvortex.com/zerothread?id=2692757

!!!Stating the obvious here, but anyone trying this needs to proceed with extreme caution - typically when your car is in "boost" (under pressure) your are tucked nicely away in the '****-pit'. PLEASE be careful when doing this, as a hose could come loose at a time when your face is burried in the engine bay looking for leaks - if it hits you it could cause you A LOT OF PAIN!!!

 

[metricspaces]

Anyone know if Audi parts say that the part is on exchange - is this a refurbished part or a brand new part?

 

[metricspaces]

Got my MAF replaced yesterday - on exchange part. Also noticed that the MAF was changed 4 years ago by previous owner.

I haven't noticed any difference in the power, but haven't gotten around to doing any logging with VAGCOM yet.

However, I'm not sure if it's safe to push it to the redline now...

Today I stopped of somewhere after driving for about 20min. Came back out, started the car up, heard a little strange grunt sound for about 1 second...then a puff of white smoke came out the exhaust!!!

I drove the car home, seems to be pulling the same as the previous day, no increase in engine temperature, no visible loss of oil, coolant all seems to be there and clean.

What you guys reckon? Is it still safe to drive?

Could my turbo be on the way out...hence the lack of power?

 

[badger5]

if logging, remember to log block 002 to see what actual airflow you get..

target is >173g/s for 225bhp (roughly)

 

[metricspaces]

Yep, plan was to log 002 on it's own first.

Then log 002, 115, 120.

Then do 032 on it's own.

But I'm not sure it's safe now after getting the puff of smoke from the exhaust, what you reckon?

 

[metricspaces]

if logging, remember to log block 002 to see what actual airflow you get..

target is >173g/s for 225bhp (roughly)

I'm APY so 210bhp...is the target still > 173g/s?

 

[metricspaces]

Got my MAF replaced yesterday - on exchange part. Also noticed that the MAF was changed 4 years ago by previous owner.

I haven't noticed any difference in the power, but haven't gotten around to doing any logging with VAGCOM yet.

However, I'm not sure if it's safe to push it to the redline now...

Today I stopped of somewhere after driving for about 20min. Came back out, started the car up, heard a little strange grunt sound for about 1 second...then a puff of white smoke came out the exhaust!!!

I drove the car home, seems to be pulling the same as the previous day, no increase in engine temperature, no visible loss of oil, coolant all seems to be there and clean.

What you guys reckon? Is it still safe to drive?

Could my turbo be on the way out...hence the lack of power?

Anyone had any similiar experiences to this? Reckon it's safe to drive and do a MAF test up to the redline? Any advice appreciate! Thanks.

 

[badger5]

I'm APY so 210bhp...is the target still > 173g/s?

yes.. would expect it closer to 180g/s

you logged it yet?

 

[metricspaces]

yes.. would expect it closer to 180g/s

you logged it yet?

Thanks. Haven't logged yet. Worried about the white smoke that came out of the exhaust! Will take a look over it tomorrow and think about doing a run with VAGCOM. Will update then with my new figures...

 

[metricspaces]

Ok, so I've replaced my MAF and done some logging again. I'm a good bit happier now.

From what I've read, my MAF readings should max out at approx 80% of the value of my BHP. My ideal BHP is 210. That means my ideal max MAF reading should be 168 (210 * .08).

I'm getting a max MAF of 165. So that would equate to 206.25 bhp. Which seems near enough to the ideal figure of 210 bhp.

I'm get a max of 267.5 NM of torque. Which matches up well with the ideal figure of 270 NM.

Going on the Ross spreadsheet for block 120 I get the graph below for the data.

What do people think? Do my values look OK? Does anything seem out?

Any feedback appreciated! I want to get a remap...so want to be sure I'm as close to stock as possible before I get it done.

 

[metricspaces]

In addition to my MAF readings. I'd be interested if anyone could give me advice on my boost (requested Vs actual).

From looking at this thread here http://www.audi-sport.net/vb/showthread.php?t=28459&highlight=Press+Intercool the formula for working out your PSI seems to be ('Press @ Intercool' -1013.25)/1000*14.50377) . This gives me a max PSI of 11.4. Which seems low from what I've read.

Also. If you look as my actual versus requested boost, you'll see that I'm not actually getting my requested boost until I hit 4000 revs. Up until this point I'm between 25% and 30% down on the actual boost I am getting versus the boost I'm requesting.

I've done a few runs and this seems to be consistent behaviour. In low down revs I'm just not getting the boost I'm requesting. I thought by 2.5K revs I should be getting what I'm requesting?

 

[metricspaces]

Here's my info from block 115 graphed out. Cmd Pressure and Press @ Intercool.

 

[badger5]

I've done a few runs and this seems to be consistent behaviour. In low down revs I'm just not getting the boost I'm requesting. I thought by 2.5K revs I should be getting what I'm requesting?

nothing other than thats the physical inertia to get the gas flow to start the turbo spooling.. not a problem as i see it.
your airflow readings look low for stock to me

clean airfilter? no obstructions?
exhaust ok? cat not choked or blocked?

 

[metricspaces]

nothing other than thats the physical inertia to get the gas flow to start the turbo spooling.. not a problem as i see it.
your airflow readings look low for stock to me

clean airfilter? no obstructions?
exhaust ok? cat not choked or blocked?

Do my figures not look OK? The Rosstech spreadsheet for block 120 says I'm getting 206bhp, which seems near enough for a 10yr old car.

Do my boost figures seem low?

How serious a problem do my MAF readings look? You mentioned previously that the aim for a 225bhp was > 173g/s. My max reading is 165g/s. That's 4.5% less than 173g/s. Doesn't seem too off?

How do people know what the ideal max MAF reading should be, and what the ideal readings should be for other blocks? Is there documentation for each particular engine?

If >173g/s is the aim for a 225bhp engine, should it not be lower for a 210bhp engine?

 

[badger5]

if its that close, why are you posting so worried about it?

 

[metricspaces]

if its that close, why are you posting so worried about it?

First off, I haven't a clue about this stuff, so thanks for the help & advice so far. I'm just trying to get to the bottom of this, make some sense of all the info that's out there, and get my car sorted so I can get a remap done

A few things that confuse me at the moment...

1) The Rosstech spreadsheet for block 120 is telling me I'm now getting 206 BHP and 267.5 NM of torque.

This matches up well with the figures for BHP and Torque here http://www.parkers.co.uk/cars/specs/Detail.aspx?deriv=16780

But from your experience an S3 should be giving close to a max of 180 g/s from the MAF. Other people on here also seem to be getting 180 (not sure if they have 210 BHP?).

So is the Rosstech spreadsheet inaccurate?


2) My boost figures seem OK? And I'm getting all the boost that's being requested when I went above 4K revs in 4th gear.

With my MAF readings low, should I be expecting an effect somewhere else? Like should I be expecting my boost to be low?


3) The formulas people are using to estimate max g/s from bhp and vica-verse don't make sense.

I've 210 bhp. So 210 * 0.8 = 168 g/s

Even with 1.25 or 1.3 that still gives a range of 161 - 168 g/s based on 210 BHP.


4) If my MAF readings are low. What effect should that have elsewhere?


And finally is there anything else I can do to help diagnose the problem here? I don't know anyone with an S3 that I could get a MAF off that I know is getting 180 g/s. The airfilter is brand new. I can get the cat & exhaust checked. But if there's anything else people can think of to help me get to the bottom of this that would be great, thanks.

 

[S3 Nattie]

To me your MAF readings look fine. I got a 210 AMK and done some logging yesterday and I did get a max of 180 g/s.

My passenger visually watched it recording to see what max air flow I get, because VAG-COM records in set intervals and doesn't always record your max value. However it did record a max of 175 g/s, but I do have a Green Cotton cone filter inside a smoothed airbox which might be why im getting 180 g/s, which equates to more than 210 bhp.

I would forget your MAF and move onto logging something else.
Not sure but some people log their duty cycle to check if their waste gate is working right, you could give that ago.

 

[badger5]

it does'nt sound way off.. so if your only concern is its not healthy enough to get a remap, then go for it.

you are comparing vagcom results which are within reasonable limits on derived torque load request.... but your airflow is not as high as some.. but not oh my god low either

eg: a few years ago i had a 225 TT come to me for revo trial.. owner had just bought the car, and did'nt know what it should go like, but had the "feeling" it should go better.. anyhows, i logged the car before flashing aything and it read 109g/s max airflow.. clearly no where near what a 225 motor should produce. no fault codes, and nothing his audi dealer would do anything about either!... we added a log i did and gave it to them, and still nothing. i fitted a known dead maf, popped a faultcode and only then would they accept it needed a new maf. all was fine thereafter. he thought i had stuck revo on it at that point such was the difference in performance. i had'nt, just got it to 225

yours is'nt that different.
i suspect you are fretting about something minor if real at all. these engines do vary from what i see. some higher, some really high some avg.