Skip the auto shop - Our mechanics make house calls

Q: No power. Only uses bank 2 to fire

asked by on

Hi guys. I got a 335i. The customer complaints was the engine warning light. I diagnosed the car only to find that it is out of timing, got special tools, I timed the car I started the car all was well then I switched off the car when I started the car again it didn't have power it is misfiring when I unplug coils from 1 to 3 the car doesn't respond when I check the spark it there, I swapped the coils around still nothing, so basically the car is only using 3 cylinders 456. Can it be the MAP sensor on the intake manifold?

My car has 25000 miles.
My car has an automatic transmission.

A: Hi there. It would be helpful to know the y...

Hi there. It would be helpful to know the year of the car in this case to supply the most accurate information. If it were the map sensor, then it would affect all cylinders. Try checking the spark plugs for damage or signs of wear.

Which timing was off, ignition or camshaft timing? I'm going to assume it was the camshaft timing since modern vehicles don't typically have adjustable ignition timing. Assuming it is camshaft timing, it is very likely the valves in the inactive cylinders have been bent. You can check this by putting compressed air into the cylinder with the piston on top dead center.

This is commonly called a cylinder leak down test. Ideally you should only use about 50 psi. Much more and the piston will move and open the valves. The valves need to be closed for this test to be accurate. If you must use shop pressures of 90 to 150 psi, hold the crankshaft by whatever method you can devise.

Once you have the piston at top dead center with compressed air in the cylinder, listen at the tail pipe, intake manifold with the throttle valve open and in the crank case. Usually the best place to listen in the crank case is by removing the oil filler cap. You are listening for the hissing sound of air passing past the intake and exhaust valves or the piston rings in the case of the crank case. If you here an obvious hiss, you have a leak in one of the mentioned parts.

Bent valves are very common when camshaft timing becomes off. This car has VVT (variable valve timing). With this in mind you should make sure that the camshaft is timed correctly.

If you should require further help getting this taken care of, have a certified professional diagnose the loss of power issue for you so that this can be properly addressed.

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

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: A bunch of warning lights just came on following a minor accident

With the vehicle being involved in an accident, there can be damage to wiring and/ or sensors, particularly if the radiator was impacted in even the slightest. Make sure the coolant level is correct. Even with the level correct, there...

Q: Difficult startup with a lot of idling when it's cold

One of the main things that can prevent a vehicle from starting in the cold is the battery. Batteries for automobiles are rated by cold cranking amps. This measurement is the amount of amperage the battery can produce at zero...

Q: My 1988 Chevrolet Silverado 1500 has power in reverse but spits and sputters with hardly any power in drive.

Hello and thank you for your question. Sounds like the manual valve is out of adjustment and the transmission is applying the forward and reverse input clutch at the same time. This will cause the issue you are having. You...

Related articles

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
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...