[335itis]

Couple days age Service Engine Light came out i scanned the car came out to be cylinder 2 and 3 misfire. I took the coils and swapped cylinder 2 with 1 and cylinder 3 with 4. cleared the codes and reset the ECU. Today the light came up again, I scanned the car and it came out to Cylinder 2, 3 and 4 so that means the ignition coil was failing, but why it still shows the 2 and 3?

In addition, I replaces all spark plugs 4k miles ago. I am running Cobb V3 AP

Do you guys think it still shows cal. 2 and 3 cuz it showed before?

I'm hoping its just the ignition coil.

[335NJ]

Did you clear the codes after swapping the coils?

[335itis]

yeah i did.

[Tomczyk]

Use some fuel injector cleaner from lucas oil. It works every time the cylinders are misfiring in my car. i thought it was the spark plugs to but i replaced them 1k miles ago. and it still showed up. and i didnt feel any power loss in my car so i knew it wasnt the spark plugs or ignition coils. So i used some fuel injector cleaner and the service engine light turns off by the next day and runs great.

[335itis]

Originally Posted by Tomczyk

Use some fuel injector cleaner from lucas oil. It works every time the cylinders are misfiring in my car. i thought it was the spark plugs to but i replaced them 1k miles ago. and it still showed up. and i didnt feel any power loss in my car so i knew it wasnt the spark plugs or ignition coils. So i used some fuel injector cleaner and the service engine light turns off by the next day and runs great.

hmm... really?! will give that a shot lol

[BIMMER_Tech 631]

Originally Posted by 335itis

hmm... really?! will give that a shot lol

How many miles on the car, if it has high mileage, more than likely the misfires are being caused by a carbon buildup and the car will require a walnut/carbon blasting. Misfires in several cylinders, along with a rough idle and stumble on acceleration are all common symptoms for this.

However, since you are running a tune, there is a couple of possibilities as well.

1. When running any tune, JB4, Cobb Etc... it is common knowledge to cut in half all stock ignition components, meaning if BMW states their plugs will last 100k, with a tune you want to replace them around 50-60k, same would go for coils. I have dealt with both first hand and on customers cars ignition coil failure simply due to the fact that the car is tuned and being forced to work harder ignition wise than normal.

2. Another common occurrence with these vehicles, is a VANOS solenoid issue, causing misfires. There are 2 VANOS solenoids on these cars, an intake and exhaust (intake on top, exhaust on bottom) located on the front of the head directly under the engine cover. These parts contain a small spring and are controlled by oil pressure. From time to time with age, and especially on the turbo models, the oil gets thick, black or even chunky, and will clog these solenoids. Since they are mechanical, the only way to properly fix them is to replace them, however there are two things, 1. You would most likely have a VANOS related code stored in the ECU, but is sometimes not visible with a generic OBD reader. Here are fault codes you may have if a VANOS solenoid is causing your problem, 2A9A Cam sensor, inlet signal invalid for synchronization, 2A98 (P0016) Crankshaft intake correlation value outside ref range, 2A82 intake VANOS jammed mechanically, 2A9B exhaust camshaft sensor signal invalid for synchronization, 2A99 (P0017) Crankshaft position sensor and exhaust camshaft, correlation value outside reference range, 2A87 exhaust VANOS jammed mechanically.

If this is the case, it is sometimes possible to remove, clean with compressed air and carb cleaner and replace (while swapping exhaust with intake solenoid) to either pinpoint which solenoid is bad or eliminate the problem all together.

[e_nice1803]

Carbon blast is what you need my friend.

[335itis]

walnut was done at 65k currently at 88k

[BIMMER_Tech 631]

Originally Posted by 335itis

walnut was done at 65k currently at 88k

If you want to come by me, i have diagnostic equipment and can look further into the issue.

[335itis]

Originally Posted by BIMMER_Tech 631

If you want to come by me, i have diagnostic equipment and can look further into the issue.

this is so weird i haven't done anything to fix this issue and the light went away yesterday.

[BIMMER_Tech 631]

Originally Posted by 335itis

this is so weird i haven't done anything to fix this issue and the light went away yesterday.

Up to you if u want dm me ur # and I'll text u