Sudden rough idle

[bcredliner]

Otto is a real person. He is the guy narrating the video and doing the work. If it is what it is why doesn't anyone say it is what it isn't-- is it? What it is--a reliable source, certainly not infallible but neither are any one of us. I vote for Otto. He has much more on the line and if he is wrong someone would have let him know and it would have been corrected. Feel free to call him and get one of you straightened out.

The data is the data, ummm, yes, and that alone is confusing because what else could it be? When I can find directions to get the data I still have to know how to interpret the data or it is just mumbo jumbo. Sure analysis of data, assuming one is adapt at doing so, is a good problem solving method. All I'm saying is there are other ways to get to the same place.

Correct, smoke testing is easy but since it does require some equipment and the next step is diagnostics I figure I might as well have the tech do the test before the diagnostics. Scotty is another good source for DIY methods. https://www.youtube.com/watch?v=zMok2y05jNE

[Ricky Bobby]

Otto is definitely a real person - dude on this forum just bought his old X5 about 2 weeks ago - its a 3 pedal MT X5

[jfoj]

Food for the trolls. See link below for Diagnostic Reports, before and after clearing codes with a standard/generic OBDII App/tool.

https://www.dropbox.com/sh/u9fnmfxe7...WfcZ88rMa?dl=0

I finally got around to grabbing some Diagnostic Reports that CLEARLY show that Fuel Trims are not reset when clearing codes on an OBDII vehicle.

This happens to be from an E70, it is what was easily at hand and had the SES/CEL/MIL on.

Note on these 2 reports were captured less than 1 minute apart. The report for when the codes were cleared shows 24 seconds of engine run time and 0 miles driven. The Non-continuous Emission Readiness Monitors are all incomplete. Note that the Long Term Fuel Trims were EXACTLY the same before and after clearing the codes.

In order to zero out the Fuel Trims a tool that will Clear/Reset Adaptations is required and this is a separate step beyond "clearing codes". This can either be a Pro level scan tool or a BMW specific tool or software that supports this feature. Fuel Trims are not impacted by clearing codes with a standard/generic OBDII tool or App.