Their average is pretty accurate. My car with 13k miles is averaging around 30mpg overall.

 

Engine mods?

 

Factory tune & M-performance intake (MPPK) & performance exhaust (MPE). Advertised by BMW at 343HP vs 300HP stock. Have not bothered to have it dynoed so don't know what the WHP is.

Its a bit quicker than my 335is performance version was pure stock & that dynoed at a base line 321WHP before I modified with 3rd party equipment to 410WHP.

 

Kevin... Speaking of the JB4 tune etc..on your 2011.

You stated..

"An issue I was having under warranty that could not be solved by the dealer caused a case to be opened & an ECU dump to be sent to Germany for resolution. It was resolved without the possibility of a piggy back tune being brought up.

Since the fix cost a few thousand I am sure they looked very closely."

So what ever happened here...

 

Nothing, they just replaced the injectors & moved on. JB4 had nothing to do with the problem, they had a bad run of injectors.

Dealer did not do a good job troubleshooting the problem. They did what we used to call troubleshoot by parts replacement.

It was once said you can't fix stupid. Symptoms were obvious to a blind man with a nose. Car does not start after sitting over night without very long cranks. Car starts white puff of strong fuel smelling exhaust smoke comes out. Engine levels out & runs great. BMW had a string of bad injectors (changed supplier) that stuck open spilling fuel into the combustion chambers temporarily fouling the plug.

First thing you look at. Problem with the modern tech is if the computer does not show the problem they are stuck. Most are just parts changers & not mechanics that can diagnose problems.

 

travel in the middle of a "car train" and you can see good mileage. my 02 CL-S will get 34 easily that way.

 

Well played again Kevin Talking about Chapel Hill Performance BMW for incompetently jerking you around on your 335is. Seem to remember you talking about two weeks’ time and two times return the car for walnut blasting valve job, a number of replacement parts, throttle position sensor etc.. Interesting, sending the ECU dump from a JB4 Beta tester to BMW Germany to diagnose warranty work. How long did it take to remove the piggyback and what else to make the car appear stock? Did you get them to replace the other 3 of the 6 six injectors later since you knew they should have just been replacing them in the first place because that a bad supplier part?

 

Did not realize injectors were more than 2 bills each just for the part. Wow

 

Forgot to answer this:

No the other 3 were good. Actually 5 of the 6 were good but the maintenance policy is to swap out the whole bank.

They had a warranty recall on the injectors but my VIN number was out of range & it never came up so it would not have been in their system. Might have been an orphan unit that was floating in the assembly supply system

I could swap the piggy back in/out in 20 minutes hood open to hood close. Longest part was pulling all the plastic covers & cabin air filter package to get to the ECU casket. Once you get to the ECU it all unplug & plug back in.

Dumb thing is if they had tested the injectors in the first place the whole deal would have taken them about an hour.