Can someone answer this please
 

My car has been fully decat and has a cone air filter on it now my question is if it hadnt been mapped would it run awful or wouldnt it make that much difference doing the decat and filter?

Your car will need a remap for these modifications. Having a decat and induction kit your AFR(air fuel ratio) will need to be changed as well as boost levels,wastegate duties ect. If these aren't mapped into you mods then you may well be running a lean or rich mixture which will cause engine damage.
I'm no expert but there are good experts who are members on here and will be abel to explain better than me

Running rich is basically a waste of money and poor performance. You can also get bore wash in extreme cases leading to premature wear.
Running lean is just going to be a waste of money :D (= rebuild in case you hadn't guessed)

Hi first thing has your cone filter come with a pipe that you fit the MAF sensor into? - - YES then your MAF sensor scaling is all wrong so that puts your fueling off in all areas and the ecu will not be able to compensate the differences in all areas of the tables to keep running safe - Also with the different pipe length and diameter and the free-er flowing air filter you will more than likely have more air coming into the engine than the ecu is being told by the MAF sensor, this will weaken your fuel mixture which increases combustion temps and will melt your pistons.

Keep off boost until mapped and you SHOULD be ok depending on the level of change you made to the inlet!!

I don't think anyone is trying to say that a different colour pipe will need a remap! Are you trying to say that having an induction kit and a full decat will NOT require a remap and will have no affect on fuling,timing,detonation ect?
Im sure you would be in a minoraty if you are :wonder:

IMO you're missing the point. With a decat fitted and removing exhaust restrictions the turbo will be going into overdrive and this is what will create overboost and lean conditions.
If you have to ask what engine damage can result from running lean conditions, you perhaps shouldn't be taking the pi55 out of people who are trying to help.

I'm no expert in this field, but.... The Decat will certainly reduce back pressure, thus cause over boosting, and the induction change will also have a radical effect on the induction temp, yes the MAF will certainly try to monitor but the chamber and density is all now different to what the Maf is trying to read?

OK so i refrained from commenting on these but as you obviously have no understanding in this area and have tried slating me then why refrain.

Why even comment on a thread like this when even a monkey who knows very little about engine but did a community college course for 6 weeks can tel u the damage caused by lean running

[/QUOTE]Also, isn't the AFR managed in open loop mode from O2 sensors and MAF readings? As I understood it, the map will only have effect in closed loop while warming up till the O2 sensors gets up to temp.[/QUOTE]

No AFR is not managed in open loop by the o2 sensors you have this completely the wrong way round so for your future knowledge.

Closed loop lambda control is controlled by reading from the o2 sensor and the ecu adjust fueling and timing to compensate for readings.

Open loop the ecu uses the defined tables in the ecu to try and achieve the target AFR.


Yes it does do u know how it measures the air flow i think not.

It uses a hot wire with an electrical current that keeps the wire at a defined temp. when air passes over the wire it cools down and the ecu has to provide a larger elec current to keep it at the same temp. it then looks at the voltage it is using to keep the wire at the correct temp and this tells the ecu how much air is flowing over it. This is determined by the MAF scaling in the Map Now if you increase the diameter of the pipe the sensor sits in then the values in the MAP table are now incorrect, as the mass of air flowing to keep atr the same temp has now changed, and therefore need re scaling.

.[/QUOTE]It doesn't matter how long/short/bendy/straight the pipe is, it measures the amount of air passing by it. It you cut the filter off entirely, the MAF would still measure the amount of airflow passing it and the ECU would calibrate accordingly..[/QUOTE]

So you increase and decrease the inlet tract on you car and see how it idles - do you know anything about inlet tract pressure waves and what effect these have on the running of the engine??? I don't think you do.




Now i didn't think going into all this was relevant and then moving onto to the effect on Boost control as i had answered the OP'S question and that was yes he needs a remap. Keep off boost until you get it sorted and you should be fine.

Now if you've nothing more constructive to add but to try and take the piss out of people who are offering genuine advice then i suggest you do one:hjtwofing:hjtwofing:hjtwofing

Could we be on for a 10 pager? :norty:

:thumb:
These kind of treads deserve at least 10 pages
a lot of us are on a learning curve into mapping and some are in denial

And engine damage from lean conditions?

Closed Loop Uses 02 sensor upto around 3k (lambda sensor) Open loop uses AFR tables within the Map above 3k

The Op homepage shows he has anew age. The MAF tube on a new age is part of the filter housing so unless he has butchered the filter housing and bodged some random universal filter to it then he will have a diff MAF tube attached ergo MAF sensor rescaling will be required. *

Missed this before my last post. 😜.

If you're really interested then the main reason for needing a map for a decat is with less back pressure there*is less energy needed for the turbo to spool. This in turn means you need less wasregate duty to achieve the boost levels targeted . so if this is not adjusted for you are likely to overboost. This I suppose is possible to control with a manual boost controller but it's not really the best way to deal with the problem.

So to get this right:

To fit an induction kit - no remap required?
To fit a S/Steel exhaust - no remap required?

Because the Ecu will adjust the Fuel/Air mixture accordingly?

So to play devils advocate, if I had a standard Blob WRX, and I wanted to fit all STI performance parts, I could install Pinks, VF35, STI TMIC, Catless UpPipe, and then I could run the car ON boost fine without risk of engine damage as the Ecu will learn and adjust the Fuel/Air mix. But to gain the benefits of the upgraded parts a remap is required?

To double the advocate of the devil I had a customer who done exactly that on a Blob WRX with 86k on it. He drove the absolute life out of it and refused to pay for a remap. He sold it recently with 133k . It never missed a beat.

well this has made it as clear as mud thanks guys lol bloody interesting read though

I was waiting for the ecu will learn the new parts and all will be ok comment.

I will try my best to explain why this is bad information.

Yes the ecu will learn but it can only still go by the calibration it has already so.

The ecu fuels the engine (in basic terms) by using a target A/F/R table. The table uses throttle position and engine load (load = amount of air getting into the combustion chamber) it then looks says ok in this cell i know i need to open the injector at this time, for this long and at this amount of fuel pressure.

1 STI pinks replacing normal wrx injectors, They have different delivery rates at the same fuel pressure so (these are just theoretical figures and are only for comparison)

WRX injector supplies 10ml of fuel when it is open for 1 second with a fuel pressure of 1.5 bar.
STI pink injector will supply more fuel when opened for the same amount of time at the same fuel pressure.

So now we are over fueling and have an A/F ration of 13.5 at cruising speeds the ecu looks at its table and goes hang on we are shooting for 14.7 AFR here so will adjust the fueling accordingly. Brilliant the ecu has now learnt this and will remember what it did and this is what will happen next time we use that cell in the tables. THE ECU CAN ONLY DO SO MUCH OF THIS SO YOU HAVE NOW TAKEN AWAY THE SAFETY MARGIN THE THE ECU LEARNING GIVES YOU.

2. Fitted vf35

The vf35 compressor map is different to the td04 so the way the turbo delivers the charge is different and will happen at a different place in the rev range.

So at 50% throttle and engine speed around 3000 rpm (again these figure are just for illustration purposes) a td04 will more than likely give a higher mass of air into the engine than a vf35 as the td04 spools earlier in the rev range.

Ecu has table which tells it at this rpm and load we should have .9bar of boost but the old MAP sensor is showing 0.65 bar.. arrrg we have a boost error the ecu then will adjust things to compensate for this again it will learn this in this particular area of the tables.

It will then have to do this across the full rev range of the engine and will be constantly adjusting this will give boost spikes and power delivery will not be as it should.

The rest of the changed items also contribute to this issue.

So, so far the ecu is backing fuel off all the time for over fueling and is constantly working to stop over boost conditions.

A car in this condition to most people will drive and pull ok. But there will be boost spikes all over the place and the power will not be what it should be. More than likely less than if you left it alone.

The ecu has these learning abilities to adjust for different types of fuel different atmospheric pressure and temps ect and to compensate for failing parts to protect your engine.

So now we have an ecu that's at or near its maximum learning capacity and we have a weak fuel pump condition, spark plugs/coil packs starting to fail and you have just filled up with a really bad batch of fuel ect. The ecu now has no way to adjust for these things and either melted pistons or rods through the block will not be very far away.

lol the mythical self learning ecu, usually a facebook subaru advice dweller.

i just wanted to know if the car would run ok without the map or if it does run ok does that mean it has been mapped

Every car is different mate and as it stands no one except the last owner can tell you if it's been mapped or not.

You need to get the car checked out, because your a perfect candidate to become one of so many we have had on here that posts a video of a knocking engine asking what's this noise. ;)

I told you before you bought this car to take your time before jumping in with both feet, now your learning the hard way why I said that to you.

Now this is the last time i'm going to tell you what to do so pay attention.

TAKE IT TO A SUBARU SPECIALIST WITH A ROLLING ROAD AND GET IT CHECKED OUT.

:thumb:

??????????

Well reading some of the responses on here it boils down to one thing.
How lucky do you feel? :Whatever_

In my book, why take a chance. The people telling you 'It will be allright' aren't the ones who will have to shell out for repairs if it turns out you're not so lucky. Are they?

What was that?
Oh yeah,
TAKE IT TO A SUBARU SPECIALIST WITH A ROLLING ROAD AND GET IT CHECKED OUT.
:thumb:

All parts that are changed for a different type need to be (mapped) calibrated so when the ecu is using said parts for reference then it has the correct info to start with and then means no learning is needed keeping you ecu free to do its learning as per Subaru meant it to.

So the injector example fit a larger injector and to get the same amount of fuel injected you need to either reduce fuel pressure or the you could change the time the injector is open. This is done by adjusting the tables in the ROM.

You log - a road side mapper logs different parameters before and after any changes so will see differences. There are then many different ways of interpreting these logs depending on what software is being used.
You can even just use excell and create your own graphs ect. Some of the most powerful tuning tools for log interpretation are just excel spreadsheets.

Different Ecu's have different amounts of available learning. I have never actually tested any i have worked with to see how far they can go. Its not something i would like to push as when you find the limit you are close to damage..



Now i meant a fuel pump that is worn and starting to fail not a underrated fuel pump. IF calibrated correctly the ecu will try and adjust to compensate for loss of fuel pressure it can do this in a few ways but if the ecu has already had to make adjustments for fueling in that area of the map then its got nowhere to go to try and help with the situation. LEAN MIXTURE = MELTED PISTONS.

To OP

If u just want to know if it is mapped then you will need to go somewhere who can read the rom, a tuning company ect.

Come see me i will plug in and tell u.



Xline -

Try reading this http://www.romraider.com/RomRaider/I...eGuideToTuning

It will probable answer most of the questions you may have.

*cough :thumb:

I agree, and he is urging caution and get a check over.

Despite what has been said in this thread,the for and against,the pros' and the cons,the do's on the dont's'(only one member has the view of don't so far)'minority'
I am looking forward to self mapping my own car and threads like this one are very informative :thumb:
Pretty much like tuning in the old days when cars had carbs, tuning a car to get the best out of it has not changed much! It's still all about timing and fueling with a little turbo boost thrown in but now we do it on a laptop and not a crypton machine. Of corse we know the ecu learns and adjusts accordingly but having a good starting point(map) is key to getting the most out of our cars including longevity.

Oh happy days :D
Now the car has a computer and I have the carbs :lol1: