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buying a 2003 530i new to forum

16K views 333 replies 20 participants last post by  mattmar1 
#1 ·
I had been a member on the e34 forum since 2009.
I have been working with my Son on his 1994 525i touring with help from the forum.
He got in a wreck in December.
A friend is selling his 2003 530i manual transmission with sports package to my Son for $2500.
It has been well maintained and has about 180,000 miles.
We are excited to see it this coming week and being part of this e39 forum.

The clutch is original and is fine now, says the owner.
I expect we will be replacing it at some time.
How long can a clutch last if driven by a careful adult?
I am a decent mechanic.
Is it a difficult job?

How does the e39 compare, in general with the e34, as far as doing work on them?

We buy it next week.
 
#316 ·
https://www.obd-codes.com/faq/fuel-trims.php

This seems like a good, simple explanation./
Even has a nice analogy.

My confusion has to do with the scanner screen.
There does not appear to be any industry standard for terminology.
But what about simple data numbers?

The screen shown in the article link shows STFT as a percentage.
Creator 310 uses the term "Adaptation, mixture additive" instead of STFT and does not indicate if the data numbers are in percentage.

The screen shown in article link shows LTFT as a percentage.
Creator 310 uses the term "Adaptation, mixture multiplicative" instead of LTFT and does express data numbers as percentage.

Can I assume that the Creator 310 is expressing data for "additive" (STFT) in percentage also? Why don't they indicate that on the screen?

OK, so this is confusing is each scanner uses proprietary language.
But what about numbers?
The scanner in the link shows percentage in a decimal format.
The example screen of Normal STFT shows 2.3 %
If the Creator 310 uses the same format, then my numbers are all under 1.0 %
My STFT ranged from 0.04 % to 0.12%.
My LTFT ranged from (Bank 1) 0.0 to -0.1 and finally to 0.2 %
My LTFT ranged from (Bank 2) 0.0 to 0.1 and finally to 0.6 %

If these numbers are correct, then I am very near zero consistently.
This would indicate, near perfection. If I understand all this correctly.

OR, does Creator 310 use a different numerical format, with 1.0 being 100% and therefore 0.6 would actually be a full 6%.
They sure don't make it easy to understand.

Once I figure this out, I can get onto the 02 sensor data.
 
#319 ·
For the fuel trims:
Ignore units, it is reporting percentages/change of some sort.
I don't know what your screen is showing. For mine it shows true %.
Yours sounds like possibly Less the x100 to get percent but :dunno: screenshot?
The fuel trims are adjusting injector "on time". +FT means more on time means more fuel and vice for -
 
#320 ·
Electronics Electronic device Technology Gadget Screen


This is a screenshot of the Creator 310 Fuel trims as it
appeared at the end of the test drive.

In the additive (STFT) I do not know what ms signifies
I realize, now, that mu is just the beginning of the word multiplicative but originally
associated it (mistakenly) with the ms because of proximity.

Are the numbers percentages?

This bit of information about additive and multiplicative values seems to differ from
the add=STFT and multi=LTFT.
I suggestst that add =idle and multi= all other driving conditions.
http://wiki.ross-tech.com/wiki/index.php/Fuel_Trim_Info

I'm surprised at how difficult it is to find an answer.
 
#323 ·
I was just searching around.
I cannot understand why different terms would be used by different manufactures to describe similar things.
To me it seems like the use of the words .....street, boulevard, avenue, lane, road, etc are slightly different but interchanging them does not fundamentally change the concept of
a thoroughfare for carrying automobile traffic.
But if someone uses the avenue to describe a conduit used by trains, it gets confusing.

Why would BMW use the word "additive" to describe STFT while VW uses the same word to describe fuel trim at idle only?
Both of these words are used to as description of fuel trims but mean different things?
There is something very wrong if that is the case.
 
#325 ·
I just reviewed the video that I had posted on fuel trims.
As I understand it:
The STFT responds to a lean or rich condition immediately and the LTFT becomes the the new baseline.
Lets say at 15% added fuel.
So LTFT should appear as 15%.
The STFT then returns to 0%.
The 02 sensor is showing 14.7 to 1 ....oxygen to gas ratio has been restored.

During my test run the LTFT started out at 0 and went to Bank 1/ -0.1 and Bank 2/ 0.1 and after a while went to 0.2 and 0.6, respectively.
The STFT ended the test run Bank 1/ 0.10 and bank 2/ 0.12
So should the Creator 310 show the new baseline LTFT as Bank 1/ 0.10 and Bank 2/ 0.12?
STFT should now be 0.0?

The numbers did not change very often during during the run.
I hope to get the car again soon and monitor the 02 sensor on the next test run.
 
#327 ·
Larrick- read the percentage as percentage. 0.6 is 0.6.
STFT needs to be maintained long enough to be valid. It is meant to adjust. Enough recordings of a STFT and the LTFT is recorded.
No, I don't know how long or how often before it records.
LTFT is retained in stored memory. STFT normally is not.
No offense, but if you aren't getting it by watching the vids and reading the articles, I don't think anyone on the forum is going to be able to explain it.
Stop worrying about fuel trim and figure out the loose coil/plug. That could be the cause of the misfire.
 
#329 · (Edited)
those are very good fuel trim numbers that you have. trim numbers are just the value of the compensation made to reach the ideal combustion ratio depending on variances in the engine operation. the long term numbers are the dme establishing a new baseline based upon the precat 02's readings. the ltft is nominally at 0, and the car adjusts it to set the baseline number and stores it. it can be varied by the dme, but it takes a while, such as if one developed a vac leak. it would change over time and increase the long term trim to compensate the mixture seen by varying the injector on times. the short term trims are the "at the moment" adjustments, lots of variables involved, engine load, fuel quality etc etc at that instant in time.. the ltft and stft for each bank are to be added together for total trim numbers of that bank. fuel mixtures are not your problem.
 
#330 ·
I do believe that I understand fuel trims.
If, from what I have gathered from vids and other sources, it take a 25% deviation from normal to produce a check engine light:
And I have a maximum deviation of 12 one hundreths of one percent... Yes, I am in good shape.

But when I am told to ignore the fact that Creator 310 shows Additive (STFT) as ms (milliseconds) but they really mean %, I get confused.
When information which I research either conflicts or at best, does not confirm other information, I get confused.

When, after weeks of searching, I still cannot define smooth running values in a simple fashion, I get confused.
Albert Einstein, famously stated; If you cannot explain something to someone in simple enough terms for them to understand it, then you do not understand it yourself!
I have always lived by that statement.. it is humbling.

I mean no disrespect, but how is one meant to feel confident when there is so little information and when that information is analyzed, much of it is conflicting.
I applaud TAB for trying to formulate a comprehensive Creator 310 user guide. It is sorely needed.
 
#332 ·
In bmw, there are 3 trim numbers, and work a little differently.
Additive and multiplicative are both "long term" trims. Additive is calculated from idle and low load, and multiplicative is calculated from high load situations.
"Lambda integrator" is similar to the "stft" used in other cars, and it's shown in %, just as multiplicative trim. Long term trims don't seem to jump around as much as they do in other cars.

Hope this clears up a bit.
 
#331 · (Edited)
you might give the torque app a try, its 6 bucks, and an obdii bluetooth adapter, 10-20 bucks, if youre android. its pretty much in plain englese, very easy to understand, and gives superior graphing capabilities to the 310. dashcommand iirc for apple. its obdii generic though, whereas the creator is BMW specific, i dont know how to explain rough running values more openly to you than i have, as with TAB im still fairly new to the BMW world, you might want to give INPA a shot.
 
#333 ·
Interesting.
I am looking at a 2003 530i now since the new one was in a wreck.
Makes a great parts car now!
I checked the fuel trims with the Creator 310 yesterday (before your post)
The multi was much higher than the add, which I assume is expected.
The multi was 7.5% as I remember.
I think it take 25% to set a check engine light.
What do you think of 7.5%
When you clear codes, does that effect the trim values?
Do they reset at all for a new reading?
 
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