No Oomph.
 

Intermittent loss of torque. No codes, stored or shadowed. Truck goes flat below 3000rpms, acceleration is poor. Vanos has been rebuilt within the past 10K miles. I've replaced both intake and exhaust CAM sensors.

Again, this is intermittent. Some days she runs like a raped ape, plenty of seat of the pants get up and go. It's very noticeable.

I'm thinking MAF - BavAuto has the VDO/Siemens for about 200 bucks. These don't last forever - and I'm looking at my original one right now. Cleaned it with CRC but really no difference.


Worst case - busted cat internals, blocking flow? Yeesh.

Possibly gasoline brand and Fuel filter?

Just did the filter - Been up and down the east coast fueling up everywhere, so no 1 particular brand, always 92+ octane.

Check the DISA Valve.

Brand new OEM german made DISA.

Cleared ALL my adaptations.. it's been good for the past few days, pulls nice and hard around town. I need to start logging and comparing when shit acts up I figure.

Anyone have input on BMWLogger?

BMWLogger – BimmerSoftware.com Don't really want to drop $60 on a logger if it's junk. The demo only lets you read codes.

Paging Otto to see what else he did besides rebuild the Vanos - that is really weird.

Hows the air filter - OEM? intake with aftermarket filter? cleaned recently?

Maybe he didnt reset throttle adaptations after Vanos rebuild? If the plugs/coils are good and fuel pump/filter is good - Idk

AFE Pro filter, brand new.

MAFs go bad, or get lazy without throwing codes from everything I've read.

A bad maf symptom would be the truck struggling, as if it's not getting enough air or fuel - correct?

If you suspect the MAF is bad unplug it. Doing so will cause the computer to use default values. It won't be optimal, will illuminate the CEL, but will allow the vehicle to drive pretty much normally.

Drove around with it unplugged yesterday, just to watch its behavior. Never threw a CEL.

I hooked up INPA, and looked at Error Memory - it was in there - but never threw on the light.

It was running fine, before, it was running fine with the MAF disconnected.

I guess I'll have to wait until it starts accelerating like shit again.