[Happy Motoring]

Curious how often people are cleaning their MAF sensors, if at all.
I recently got the air mass too high code 102001 and some people were suggesting to clean the sensor. It seems most that need to clean are folks with aftermarket intakes. I have a stock intake and hem filter so not sure why the sensor would be that dirty but I cleared the code and everything has been fine so far. I will clean it over the weekend and hope this isn't anything serious.

[F87source]

Yes I personally clean my MAF sensor every air filter change with maf cleaner. It is just personal preference but I always keep my cars extremely well maintained compared to the average or even enthusiast owner, so it is a small touch to keep everything running at 100%.

Becareful when you are cleaning it that you don't drop the sensor, and don't touch the wires inside of it. Also when you are unclipping the MAF sensor use a small flat head to lift the connector gently so it doesn't break.

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Originally Posted by Happy Motoring

Curious how often people are cleaning their MAF sensors, if at all.
I recently got the air mass too high code 102001 and some people were suggesting to clean the sensor. It seems most that need to clean are folks with aftermarket intakes. I have a stock intake and hem filter so not sure why the sensor would be that dirty but I cleared the code and everything has been fine so far. I will clean it over the weekend and hope this isn't anything serious.

A dirty sensor will never read too high. It will read lower than normal.

That is, *if* the sensor actually needs cleaning. There's a big controversy if it actually does anything. Hot film MAFs are self cleaning anyways.


Is your car tuned?

[F87source]

Originally Posted by Enabled

A dirty sensor will never read too high. It will read lower than normal.

That is, *if* the sensor actually needs cleaning. There's a big controversy if it actually does anything. Hot film MAFs are self cleaning anyways.


Is your car tuned?

MAF is only used in idling conditions and low load conditions only iirc, so you'd only notice harsh idling.


If conditions are dusty enough and your air filter isn't sufficient in it's filtration capabilities or if it's so saturated with dirt it will let the dirt by. Then that dirt will end up on the maf and cake the maf despite it's supposed self cleaning ability. You can't bake dirt off.


I've seen some dusty mafs from bmws, I'd keep it clean before it gets so bad with dust getting suck in every crack you can clean it anymore.

[Happy Motoring]

Originally Posted by Enabled

A dirty sensor will never read too high. It will read lower than normal.

That is, *if* the sensor actually needs cleaning. There's a big controversy if it actually does anything. Hot film MAFs are self cleaning anyways.


Is your car tuned?

BM3 stage 2

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Originally Posted by Happy Motoring

BM3 stage 2

It is much more likely to be from the tune than a dirty MAF causing MAF plausibility codes.

Do you have the freezeframe data at the time of the code?

[Happy Motoring]

Originally Posted by Enabled

It is much more likely to be from the tune than a dirty MAF causing MAF plausibility codes.

Do you have the freezeframe data at the time of the code?

Are you asking for a log? I have not done that yet.
Never had a problem for years, confused as to why now. I even ran the 91 octane tune to not run into problems.

To give some context to the issue, the car was slightly stuttering at WOT. Read the codes and 102001 popped up. I cleared it and drove for a week and everything is fine.

[F87source]

Do you have an after market intake?


Unlikely to be tune related as the ECU would expect more air for the new load and boost targets. unless your tuner did an absolute crappy job, but you'd have a really poor driving car if that was the case.

[Happy Motoring]

Originally Posted by F87source

Do you have an after market intake?


Unlikely to be tune related as the ECU would expect more air for the new load and boost targets. unless your tuner did an absolute crappy job, but you'd have a really poor driving car if that was the case.

Factory intake with oem filter. Had a look while cleaning the sensor and it was clean. I've ran with this tune for about 2 years with zero issues. I haven't changed anything...

[F87source]

Originally Posted by Happy Motoring

Factory intake with oem filter. Had a look while cleaning the sensor and it was clean. I've ran with this tune for about 2 years with zero issues. I haven't changed anything...

Check your vaccum hoses for a leak.

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Originally Posted by Happy Motoring

Are you asking for a log? I have not done that yet.
Never had a problem for years, confused as to why now. I even ran the 91 octane tune to not run into problems.

To give some context to the issue, the car was slightly stuttering at WOT. Read the codes and 102001 popped up. I cleared it and drove for a week and everything is fine.

No, freezeframe is the data snapshot collected at the time of the error. It's crucial info.

I do quite a bit of tuning and remote diagnosis and this is very important.

There are MAF plausibility calculations that happen in the ecu, which would throw codes when the airflow is higher than expected... hence why I asked you if you had a tune.
It's not as simple as "raise air raise fuel".
Since you've had it for a few years, get that freezeframe data, especially from a BMW diag system. This would start showing what, when, and how.

[F87source]

Originally Posted by Enabled

No, freezeframe is the data snapshot collected at the time of the error. It's crucial info.

I do quite a bit of tuning and remote diagnosis and this is very important.

There are MAF plausibility calculations that happen in the ecu, which would throw codes when the airflow is higher than expected... hence why I asked you if you had a tune.
It's not as simple as "raise air raise fuel".
Since you've had it for a few years, get that freezeframe data, especially from a BMW diag system. This would start showing what, when, and how.

IIRC that isn't easily accessible on the F series chassis anymore, shadow codes or freeze frame data is harder to access on this car. From what I hear this is the conclusion about bmw's shadow code/freeze frame data access on an F series car:


INPA doesn't work, carly doesn't work, BAV technic doesn't work, Snap-on solus (those big full function tablets) doesn't work, and ISTA doesn't show shadow codes/freeze frame data directly. This is probably because bmw wants to protect this data as it shows critical data that can be used to deny warranty like detecting tunes (wgdc, afr, boost, trims etc compared to what they should be - can be used to detect piggy backs like car always requesting more fuel when boost targets are lower than expected). It can also be used to show abuse if you got WOT alot while cold, and drifting, money shifts etc.






If I am wrong how do you get freeze frame data? Because it has never been an option for me as I am lead to believe it isn't easy or at all possible to get.

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INPA works perfectly fine and I prefer it over ISTA. I've used it on F chassis, even on 2021 M2, and G chassis just as well.


In ISTA, you have to click on the code and one of the buttons on the lower left (I can't remember off the top of my head on what it's worded like) to display the DTC freeze frame.

INPA and Tool32 will still give more info about the codes.

[F87source]

Originally Posted by Enabled

INPA works perfectly fine and I prefer it over ISTA. I've used it on F chassis, even on 2021 M2, and G chassis just as well.


In ISTA, you have to click on the code and one of the buttons on the lower left (I can't remember off the top of my head on what it's worded like) to display the DTC freeze frame.

INPA and Tool32 will still give more info about the codes.

Yeah with ISTA the codes given are really limited, mostly just mileage. Genetic OBD2 tools don't show anything at all.


I'll see about getting INPA but it's not designed for the F series at all.

[Enabled]

Originally Posted by F87source

Yeah with ISTA the codes given are really limited, mostly just mileage. Genetic OBD2 tools don't show anything at all.


I'll see about getting INPA but it's not designed for the F series at all.

BMW engineering uses INPA every day with F, G, i chassis, and Supra too. Daily use by a couple of very good friends at development and engineering.

Obviously they have updated files regularly, but INPA was designed to be very configurable, which it is.

Personally, I use INPA because it's much faster than ISTA.
ISTA collects the same data and runs the same exact routines that INPA and Tool32 have, but in a prettier GUI for the dealer techs to use.
The main benefits to ISTA are the test plans with repair and wiring info. That's pretty much the only reason why I boot it up.

ISTA does show the freezeframe data (called environment data) but you have to bring it up intentionally.

[F87source]

Originally Posted by Enabled

BMW engineering uses INPA every day with F, G, i chassis, and Supra too. Daily use by a couple of very good friends at development and engineering.

Obviously they have updated files regularly, but INPA was designed to be very configurable, which it is.

Personally, I use INPA because it's much faster than ISTA.
ISTA collects the same data and runs the same exact routines that INPA and Tool32 have, but in a prettier GUI for the dealer techs to use.
The main benefits to ISTA are the test plans with repair and wiring info. That's pretty much the only reason why I boot it up.

ISTA does show the freezeframe data (called environment data) but you have to bring it up intentionally.

Very interesting, I'll look I to it! Thank you.