[Fuel&Fire]

So I started getting a really rough idle, for the last few weeks, only in the morning when I start the car. Well this morning, I could not get it to go away, and got a service engine soon light, and when I did a "check control" the spark plug symbol lit up. Well I figured I have warranty i'll pull the JB3 and bring it in... well when I pulled the JB3, and made sure all the connectors were in correctly it wouldnt start. It would crank for about 20 seconds, and then just stop with an ! on the dash info. So after checking the connectors a few times, and getting the same result, I figured I'd put the JB3 back on and see what happens.. BAM starts right up (with service engine soon light on). Now I have a set of Spark Plugs, and Spark Plug tool (I got it from a member a while ago) but have no Idea on how to change the plugs or if that will even fix the problem. I do have a BT tool, but my computer died (writing this from my phone) so I'm waiting for it to charge up to get some codes. Anyone ever experience anything like this? What would you do? I'm really confused why the car wouldnt start without the JB3 installed.....

BTW the car is an 07 - w/ 40k miles. I dont believe the plugs have ever been changed.

[Drakos]

The problem has to exist in your connection. You have to verify that the connectors are on secure, and seated properly on the ECU module. For the sparkplugs, you will need an extension and a 3/8 socket torque wrench set to 23nm. You will find that the sparkplug tool will not fit over the plugs. The reason is because the tool has a magnet inside it that sticks to the plug not allowing to fit over it. What you will have to do is to remove the magnet insert with a flathead screwdriver. Once removed, the tool will now fit over the plugs, but will not hold it in place. The easiest solution is to find a generic spark plug socket which has a rubber gromet insert that holds the plug. Remove this and transfer it to the tool. The job itself is very easy and is featured in the DIY section.

[Fuel&Fire]

Ok, I'm wondering if I bring the car into the dealer with the JB3 installed - (really dont want to take it apart again) if it will cause an issue if they just need to replace the plugs. Do they tear into the ECU for this stuff? I can clear the codes, and set the Map to 0.

[Drakos]

There are no guarantees here. Whether or not the tech will poke into the ecu is questionable. Think about this for a minute....You are getting rough idle, probably plugs, injectors, coils or HPFP. Why give a reason for BMW to deny your warranty because you didn't want to spend the 15 mins to disconnect your JB3? You don't know what the issue is for certain and can't guarantee that they won't look inside your ecu. I have left JB3 in for my scheduled oil changes without any issues. For warranty work, no way I would take that chance unless you don't care about warranty much.

[Mike@N54Tuning.com]

Don't take the car in modified. Just email BMS some photos of the stock install for advice.

Mike

[Fuel&Fire]

Thanks for the help guys. I gave it another try, and got it to work, guess my triple checking still missed something. Off to the dealer I go!