Skip the auto shop - Our mechanics make house calls

Q: CEL slow higher rpms

asked by on

My car is a DCT with JB4 tune and BMS intake. When I shifted at higher rpms my car sputtered and slowed down. The Check Engine Light came on the dashboard, so I turned off the engine and started it back up. Then everything was back to normal. I tried to run the stock tune and it bypassed the JB4 completely and the same problems occurred. Do you know what might be causing this?

A: Hello there, thank you for asking about you...

Hello there, thank you for asking about your 2013 BMW 135i. The very first thing I would do is have the vehicle scanned for trouble codes, as sputtering and a Check Engine Light can be caused by a wide variety of symptoms. Retrieving the trouble codes can give a clue as to what the issue may be. You mention that you have had high performance aftermarket components installed; it may be possible that they are interfering with the stock engine performance or emission systems, and causing the check engine light to come on. If you want to have this checked by a certified mechanic, a technician from YourMechanic can come to your home or office to have the vehicle scanned for trouble codes.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Car cannot start, shifter showing second gear

Your symptoms seem to be similar to the situation where the linkage between the shifter handle and the transmission range selector may be loose or broken. In this event it may seem like the transmission range selections don't match up...

Q: SES light crack noise

Hello. The symptoms you describe are actually a common known occurrence among 135i models. The 135i uses a turbocharged engine that generates high boost pressures, which can sometimes cause boost hoses to come free due to excessive pressure. I would...

Q: Check engine running rough

You may have overfilled your engine with oil and the excessive oil started to foul out the engine cylinders. Have the oil level sensor checked by having a mechanic diagnose the problem and Check Engine Light to see if oil...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...