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chrisvscars chrisvscars is offline
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Default Single Turbo 335i fuel trim problems. - 09-29-2020, 08:48 PM

Hi, so i got my single turbo 335i back about 2 weeks ago, and she drives fine, when she is at idle first thing in the morning its a little rough, but other than she drives fine.

i did a few 3rd gear logs and the car was perfect and pulled hard.

Yesterday i tried a 2nd gear pull into third and the car went into safety at around 5k rpm, and when i checked the logs i saw it was fuel trim variance.

trim one was close to 40 and trim 2 was at like 12.

Gt35 turbo
walbro 450
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chrisvscars chrisvscars is offline
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Default i fixed it - 09-30-2020, 06:25 AM

The O2 sensors where the wrong way around
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Dave @ BMS/Fuel-It!'s Avatar
Dave @ BMS/Fuel-It! Dave @ BMS/Fuel-It! is offline
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Car: E92 335XI
Default 10-03-2020, 06:04 AM

Originally Posted by chrisvscars
The O2 sensors where the wrong way around
That happens pretty often, glad you got it sorted & quick.

Throw up a log if you want some advice or a second set of eyes on it.

Enjoy your weekend & stay safe.

Burger Motorsports
Home of the JB4 the worlds most popular turbocharged tuning system!

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