soot blowback: how to fix or mitigate?

[BeemerBiker]

252,000 miles on 1996 explorer. Have K&E performance filter installed 10 years ago.
have howling noise at idle / moving. poked around and observed soot at location in picture

 

[J_C]

Fix? Clean soot out? I mean after 250K mi... it's due for it?

I'd get rid of the K&N ("K&E"?) if it's their oiled type, despite K&N reps claiming otherwise, I am sure it deposits oil film on the MAF sensor. If you can smell an open jug of oil, then there is no question that a stream of air, vaporizes and deposits it downstream.

Howling noise, I don't think that is related to the areas in question, I mean if you clean them out and it's still there (is there a honeycomb grate on this at the MAF segment?), I'd look at the throttle body, and the IAC needing cleaned or replaced.

 

[BeemerBiker]

Fix? Clean soot out? I mean after 250K mi... it's due for it?

I'd get rid of the K&N ("K&E"?) if it's their oiled type, despite K&N reps claiming otherwise, I am sure it deposits oil film on the MAF sensor. If you can smell an open jug of oil, then there is no question that a stream of air, vaporizes and deposits it downstream.

Howling noise, I don't think that is related to the areas in question, I mean if you clean them out and it's still there (is there a honeycomb grate on this at the MAF segment?), I'd look at the throttle body, and the IAC needing cleaned or replaced.

the mass air flow has been replaced twice and it is the device with the wires coming out of it on the far left. There was no soot observed in the large plastic tubing that connects the air filter to the engine intake (red arrow with text soot and howling noise). The oil blowback tube is just to the right of the MAS. My son says there is no soot in that area. When he disconnected the small end of the long tube he saw a butterfly valve that killed the engine when he closed it by hand. The howling noise was more apparent when that tube was disconnected. He saw soot in that area. He will be in town in a few weeks so I can get a better look. What is that cast aluminum device that has the butterfly type valve? Is that the IAC that is mentioned here

Ford Explorer loud howling noise from air intake possibly related to Idle Air Control Valve: Ford Explorer Miscellaneous

Ford Explorer Ford Explorer loud howling noise from air intake possibly related to Idle Air Control Valve - 78 reports. Learn about this problem, why it occurs, and how to fix it.

repairpal.com

 

[J_C]

I am not familiar enough with your 4.0L OHV intake to make enough sense out of what you wrote, so I would clean it out, and wonder if you need a new PCV valve if there's a lot of soot and it hasn't been changed recently.

It might help if you provided a better picture of the entire intake and indicated this butterfly valve. I assume you don't mean the throttle body.

 

[koda2000]

The howling at idle is your IAC. You can try cleaning it (has never worked for me) or just replace it.

I agree that K&N oiled air filters are not a good idea. The YouTube "Project Farm" guy has tested various air filters and has determined that K&N oil filters do not filter as well as pleated paper filters (and the oil can mess with your MAF). I threw away the K&N oiled filter that came in my 2001 5.0L EB years ago and replaced it with a high-end Purolator paper air filter. Wix filters are also a good choice.

Oil in the intake is usually caused by too much air flowing through the PCV valve, although with over 250,000 miles some blow-by is inevitable.