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Two different MAF values - Fuel trims out of range?

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YOUR RESEARCHTwo different MAF values - Fuel trims out of range?

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Clean didn't help)

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No successful repair reported for this finding.

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Unsuccessful attempts: 1
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Suggestion · Original poster
On my Foxwell NT530 under DME there are two different MAF values - I noticed that both of them were out of the allowed range (around 20-21.5) so I replaced MAF sensor (cleaning didn't help)
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Two different MAF values - Fuel trims out of range?

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Leading evidence: 'Clean didn't help)' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Clean didn't help)' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.

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Replace maf they are 1.11 / 1.11

Suggestion or failed attempt

No successful repair reported for this finding.

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Reported fixes: 0
Unsuccessful attempts: 1
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Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

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Suggestion · Original poster
Previously my fuel trim values were 1.18/1.18 (!) and now after replacing the MAF they are 1.11 / 1.11 which are still too high (1.02/1.03 +- 0.04/0.05)
Original post Read captured discussion
Two different MAF values - Fuel trims out of range?

Replace maf sensor (

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes: 1
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that report an unsuccessful attempt: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Unsuccessful attempt · Original poster
On my Foxwell NT530 under DME there are two different MAF values - I noticed that both of them were out of the allowed range (around 20-21.5) so I replaced MAF sensor (cleaning didn't help)
Original post Read captured discussion
Two different MAF values - Fuel trims out of range?

Frequently discussed actions (3)

These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.

Clean didn't help)

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster
On my Foxwell NT530 under DME there are two different MAF values - I noticed that both of them were out of the allowed range (around 20-21.5) so I replaced MAF sensor (cleaning didn't help)
Original post Read captured discussion
Two different MAF values - Fuel trims out of range?

Replace maf sensor (

No successful repair reported for this finding.

0
Reported fixes: 1
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that report an unsuccessful attempt: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Unsuccessful attempt · Original poster
On my Foxwell NT530 under DME there are two different MAF values - I noticed that both of them were out of the allowed range (around 20-21.5) so I replaced MAF sensor (cleaning didn't help)
Original post Read captured discussion
Two different MAF values - Fuel trims out of range?

Replace maf they are 1.11 / 1.11

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster
Previously my fuel trim values were 1.18/1.18 (!) and now after replacing the MAF they are 1.11 / 1.11 which are still too high (1.02/1.03 +- 0.04/0.05)
Original post Read captured discussion
Two different MAF values - Fuel trims out of range?

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3 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.

Rennlist: 1 discussions

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POST 1 / ORIGINAL POSTEROriginal post

On my Foxwell NT530 under DME there are two different MAF values - I noticed that both of them were out of the allowed range (around 20-21.5) so I replaced MAF sensor (cleaning didn't help) Now the other one is between 18-19 which is just within the range (17 +-2.5) but the other one of those mass airlow values is still around 20-21. Previously my fuel trim values were 1.18/1.18 (!) and now after replacing the MAF they are 1.11 / 1.11 which are still too high (1.02/1.03 +- 0.04/0.05) Any ideas what's happening here? What might be that other mass airflow value and how to fix that so that it's in correct level. Could there be a vacuum leak somewhere? If so any ideas where that might be based on the other MAF value being too high? Edit - just found this one from Renntech -> Could that be that Spec. air mass? Also both of my o2 sensors are bit high but I guess that's because of that Spec air flow being too high. What exactly is that Spec air mass?

POST 2Original post

I haven't used any Foxwell equipment, but I can tell you that the Porsche DME protocol does output two MAF values, one is "specified MAF" and one is "actual MAF" . If you have and air leak into the engine that is not going through the actual MAF sensor to be measured, the actual MAF value/reading will be lower than expected//specified value. Do you have a code? or fuel trim issue? Maybe you should post those readings for more help.

POST 3 / ORIGINAL POSTEROriginal post

It doesn't throw any codes. So those values are 1.11 / 1.11 and about -2.x / -3.x % (from my memory) - I'll need to test a bit further just in case it's still adopting new values - I did one about 20km trip so I guess it could be still learning the correct setup.

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