[c131frdave]

I have a 2007 335i that was in storage for several years. My son turned 16, so we brought it out of storage and all was terrible. At least two fuel injectors were bad, they were clicking badly and I had all kinds of trouble codes related to injectors.

The old injectors were all -1, so I replaced all of them with newer ones and that seemed to solve the problem. It runs smooth with no faults.

However, after it warms up, it starts to misfire and lag. It's not a misfire like when the computer shuts down cylinders to protect the engine, but actual loss of power. It happens after driving about 5 miles. It stays smooth at first under normal throttle, but under heavy throttle it has low power and pretty bad turbo lag and boost cutout. The longer you drive it, the worse it gets until the computer starts shutting down cylinders.

Since it runs fine when cold, I'm thinking it is the 02 sensors as it runs in open loop when the sensors are not hot enough to work, however the boost issues make me think maybe it's the vanos. Has anyone else seen this?

The gas is 3 years old, which also may be a contributing factor. Unfortunately we filled the tank before putting in it storage. I may syphon some of it out and put in new. Anyone know of a good gas treatment additive?

[swellengear]

Any codes? Vanos solenoids can get sticky if sat for a long time. Might be worthwhile pulling them out, and giving them a good clean. I would also get the old fuel out.

[c131frdave]

No codes until it gets bad enough for the computer to start shutting down injectors. It takes about 5 minutes of boost lag (or no boost in and out) before it starts "misfiring". I think I'm going to replace both O2 sensors and clean the vanos valves as well.

[lookalikehuuh]

Did you code in the newer injectors with the values from each injector to the car? When you say newer injectors can we assume you bought used injectors and not brand new index 12s?

If used injectors, did you change out the seals and decouplers?

edit: also you probably won't be able to siphon fuel out thru the filler neck. You will likely have to remove the seat and remove either the fuel pump or the regulator and use a hand pump to remove that old fuel. You really should have done that before replacing the injectors because 3 year old fuel can do a real doozy on the fuel system.