All,

Just ran a 2 day event at the local track. Car is an 04 A4 coupe that sees HPDE's and speed events about 4 times a year. Engine has Vararam and a Corsa cat back, catch can on the (non-existent from GM) PCV system....

After the first two runs, threw a P0101 code. Cleared it and it set on the second key cycle again, during a run. Pulled in, cleaned the MAF senson with MAF cleaner spray and looked at the filter in the Vararam (it has about 2 track days, maybe 3 on it and I have never oiled it; new about 3K ago). I pulled the bellows and found oil literally IN the plastic intake tubing. I understand the catch can caught some through the PCV system (a small amount in there) but this must be coming through the throttle body vent.

Heres the other thing...I mixed 100 octane fuel at the track (I knew I would be up there in RPM and did not want to detonate; figured it would do a good job cleaning stuff out too) when all this started. The fuel pump is now loud, had never made a noise before and I had mixed 100 octane before, although not as strong a mixture.

According to the Tech II a guy had at the track, we diagonsed back in the GM book and saw values for MAP to be close to correct. The checklist says the two values for MAF and MAP have to show 50% or more off from each other to throw the code. I am guessing this is just a dead sensor then?

So....here are the questions?
Did the intake oil problem burn out my MAF?
Did the fuel I used burn up my fuel pump?
Do you think the fuel pump noise "might" go away after I get back to 93 octane?

Thanks for your thoughts. I have tried to observe and tread lightly with dumb questions. I have an event at the beach in two weeks and would REALLY not like to have trouble there!

TIA,

Cassidy

 

My experience with P0101 has typically been unmetered air entering downstream of the MAF. Check for loose connections where the coupler attaches to the air bridge and the throttle body, Verify that the coupler and bridge don't have any cracks. I don't see how the addition of unleaded 100 octane would have caused any problems.

GL!

 

Thats good to hear

I wonder if the sensor just has so much blow by entering the intake via the throttle body vent to the valve cover that its tripping the code?

I had literally a pool of oil in the front of the bellows. That oil didn't get in there via osmosis so I am guessing a good bit of air accompanied it. Wonder if I have a ring issue causing so much blow by...at 12K miles...I doubt it but could.

A guy at the track (tachitup motorsports is AWESOME by the way) showed me how they do bellowed catch cans and then vent to atmosphere rather than recirc'ing into the intake. Clearly you don't need a vacuum to draw air into an LS block!

Cassidy

 

After some homework online I think there are a few conditions I need to eliminate before I take the car in for warranty fix....

The car has to be above 2800 rpm for 2 seconds to set the code, hence the fact it set on the back straightaway on the track. I think if the intake had THAT much oil in it, maybe some got into the MAP sensor too. If that is the case, the value it reads might be less/more than the MAF value based on it being damaged/clogged. I think I can take the intake off the car pretty easily in an hour so maybe thats worth doing before I do anything else?

Anyone have an opinion about whether crankcase pressure could have tripped this code?

All advice appreciated and reciprocated when I can offer input

Cassidy