Help? P04db crankcase ventilation system disconnected
 

Installed a cai on 3.5 ecoboost and i keep getting this code..
I cleared it and everytime i floor it it comes back

p04db crankcase ventilation system disconnected

anyone?

nobody lol

hmmm am i the only one getting this?

I don't have a CAI, EB, or the error code... but, the crankcase should have a breather hose/pipe that goes to the intake. If you removed or modified this breather hose then it's possible a sensor noticed the change. If your CAI didn't modify this, then it could be a bad sensor.

I sure hate to resurrect a dead thread, but it may help someone down the line. I had the same issue today. I have no modifications on the engine at all, but I had the oil changed a couple days ago and that was the issue: they didn't seat the dipstick all the way into the valve cover. It looked fully inserted, but it wasn't. I only noticed it because as I was taking the engine cover off to get to the sensor I saw what looked like a little bit of oil spray above and to the side of the dipstick, near the master cylinder and power steering unit. It wasn't hard to see where it came from after that. So make sure your dipstick is fully inserted AND that the o-ring on the end of it is intact.

#6, right above your post...

Basically, a leak into the crankcase.

My '18 3.5EB has had the same code come up repeatedly. I played with and ID'd one problem, or so I thought, and the 1st Dealer replaced the PCV sensor assy. They did mention the "manual says to replace the dipstick". The 1st time that the CEL came on was approximately 6600 miles AFTER I installed the dual filter Injen CAI. After they replaced the PCB sensor I took a drive up to Michigan and while enroute back to North Carolina and the light came on again, after about 1200 miles AFTER the new PCV sensor assy was replaced. 2nd dealer it went to told me that they couldn't find anything and it was "probably due to the cold air intake", and almost had the nerve to tell me they were going to charge me the diagnostic fee. That was very quickly resolved after I reminded them that the vehicle has less than 10000 miles on it and a cold air intake doesn't void the warranty, as well as their technical analysis made ZERO sense.

Now my question, which makes absolute sense to me, is that if I would have had a problem after I installed the cold air intake it would have occurred immediately or very soon after, not after more than 6000 miles while the vehicle was in for an oil change. Sensors are going to pick up changes in a matter of minutes if not instantly. So my question would be what else has anybody experienced or had a dealer tell them the problem was (LEGIT or BS) or try to blow smoke up their ass, with regards to this known problem. It doesn't affect everybodys truck, but when it occurs the dealerships seem to have no idea and simply looks to absolve themselves of any responsibility by saying it's your aftermarket cold air intake. Apparently simple troubleshooting is a lost art.

Anyone?

I purchased a AFE CAI. They are familiar with this Along with the kit they include a tube with an angled opening that you incert in the pvc outlet. It works.