RS2 - Engine Hesitation

[prj]

I'm new to RS2's. How do you pull the codes on this car?

You get a little tool called VAG-COM or alternatively VCDS (they were forced to rename it), and install it on your laptop.

You can have VAG-COM 409 cables off ebay for 5$ and you also need something called a "2x2 adapter".
Get one, it will be more than enough for you, and it's cheaper than driving somewhere, never mind paying a garage to do the diagnostics.

[AndyP]

I'm new to RS2's. How do you pull the codes on this car?

PS Anyone local to Doncaster willing to lend me their MAF for a few minutes???

I have a spare S2 MAF and VAG-COM. PM me if you want some help.

[steverrquattro]

I have a spare S2 MAF and VAG-COM. PM me if you want some help.

PM sent.

PS I thought the RS2 MAF is different to the S2 one?

[UrS4boy]

G70 Mass Air Flow (MAF) sensor info

I thought the RS2 MAF is different to the S2 one?

It is. (But an S2 MAF with no screens is very close). Have a read on this post:

http://forums.quattroworld.com/s4s6/msgs/20442.phtml

[prj]

It's not different.
Logged them side by side many times, AFR is repeatable to 0.1 with the two MAF's.
Please let this myth die.

Probably on that graph you posted, someone used a MAF that was used a lot, and the other one was newer.
Or the pull was slightly different due to some circumstances.

[UrS4boy]

It's not different. Logged them side by side many times, AFR is repeatable to 0.1 with the two MAF's. Please let this myth die.
Probably on that graph you posted, someone used a MAF that was used a lot, and the other one was newer. Or the pull was slightly different due to some circumstances.

Sorry. Airflow is different between the two, with respect to "negative" boost (pressure needed to get flow INTO the inlet to the turbo). The S2 (and UrS4/S6) version of the MAF with its tight stainless steel mesh is more restrictive to airflow, as detailed in Part 4 of the 5 Part AutoSpeed Negative Boost series of articles:

http://autospeed.com/cms/article.html?&A=0652

[prj]

Sorry. Airflow is different between the two, with respect to "negative" boost (pressure needed to get flow INTO the inlet to the turbo). The S2 (and UrS4/S6) version of the MAF with its tight stainless steel mesh is more restrictive to airflow, as detailed in Part 4 of the 5 Part AutoSpeed Negative Boost series of articles:

http://autospeed.com/cms/article.html?&A=0652

The airflow restriction is different yes and the RS2 MAF is less restrictive. But this is all theory.

Even assuming that the mesh is super-duper restrictive and plays a bigger role in restricting engine flow than the air filter for example, the MAFs still measure the amount of air passed through them identically, meaning same kg/hr voltage for RS2 maf, AAN maf and 3B maf - and this is the only really important thing for engine management. Thus they are interchangeable without needing a remap.

[UrS4boy]

The airflow restriction is different yes and the RS2 MAF is less restrictive. But this is all theory. Even assuming that the mesh is super-duper restrictive and plays a bigger role in restricting engine flow than the air filter for example, the MAFs still measure the amount of air passed through them identically, meaning same kg/hr voltage for RS2 maf, AAN maf and 3B maf - and this is the only really important thing for engine management. Thus they are interchangeable without needing a remap.

You are missing the my point. I will agree with you that the electronics are similar if not identical and generate the same kg/hr voltage. What you are NOT getting is it is easier to draw that air through the RS2 MAF than, say, an ABY MAF because the RS2 MAF is less restrictive to flow. Therefore an RS2 MAF will allow easier/quicker spool than the ABY MAF, for the same engine, turbo and intake manifold. There was a good reason for the engineers at Porsche to select a better flowing MAF from their parts bins than just to use the standard ABY S2 MAF.

You might still disagree. I don't care. I have an RS2 MAF on my RS2'd AAN and would not switch back (unless the RS2 MAF broke).

All the cool kids are switching to MAF-less VEMS so this arguement will very soon be moot.