Backfiring after installing K&N filter

Jason B

Well-Known Member
First Name
Jason
Joined
May 19, 2021
Threads
6
Messages
2,332
Reaction score
6,267
Location
Louisiana
Vehicle(s)
2021 XL STX SE 4x2
Occupation
machinist
I did run the K&N for a couple of months after flashing the FFP tune but then returned to the stock Motorcraft filter, not because of any (noticeable) problems, but because I was concerned about the "freer-flow" K&N letting more particles "freely flow" into my engine.
I think that's what most people mean when they say they want a CAI, because automakers have been using CAI on their engines for a long time. Even my 1995 F150 had it.
And that box OP installed is not CAI if it is allowed to draw air from the top, inside the engine compartment. That box would work with an aftermarket hood with ram air.
 

Superdannyboy

Well-Known Member
Joined
Jan 1, 2020
Threads
24
Messages
1,097
Reaction score
1,348
Location
75209
Vehicle(s)
2019 Ford Ranger XLT Sport Appearance Package

XL GT

Well-Known Member
Joined
Mar 4, 2021
Threads
1
Messages
163
Reaction score
748
Location
Manheim, Pennsylvania - Wildwood, NJ
Vehicle(s)
21 Ranger STX
Occupation
Civil Engineering Firm
I think that's what most people mean when they say they want a CAI, because automakers have been using CAI on their engines for a long time. Even my 1995 F150 had it.
And that box OP installed is not CAI if it is allowed to draw air from the top, inside the engine compartment. That box would work with an aftermarket hood with ram air.
Yeah, it sounds awfully counter-productive if it's drawing cooler air from the front intake tube, and sucking in hot air through the top under the hood. It's not really a CAI, it's kind of an LWI (Luke Warm Intake). But hey, you probably get stickers with it.
 


thomas461

Member
First Name
Pete
Joined
Jun 17, 2021
Threads
2
Messages
20
Reaction score
80
Location
Cumming, GA
Vehicle(s)
2019 Ford Ranger XLT, 1998 Ford Ranger XL (Son)
Vehicle Showcase
1
Having run a lot of different turbo vehicles for a lot of years. My experience has been until you get to the point of changing the injectors and going with a larger turbo the factory air box is more than enough. In two previous cars going to a CAI actually caused the vehicle to lose HP/TQ because intake temperatures went up. I come from Subaru's (A lot of them), Turbo Supras, Turbo Datsun/Nissan's and Ford Turbo Coupes from the way back.

For every 1 degree of intake temp you gain or lose HP. If you are pulling air from under the hood the charge will be warmer going into the combustion chamber. This will cause the ECU to do a couple of things. More fuel to cool the charge since your EGT's will rise or it will cut the timing to prevent detonation (Knock) or it may even do both. Either/or results in loss of HP from your engine.

The engineers who manufacture these vehicles know what they are doing to get "everyday" HP numbers from these engines. They design the drivetrain (Intake, engine, Exhaust, Transmission, rear end) for a board range of uses (Daily Driving, Emissions, Towing, MPG, etc). CAI intakes are an expensive way to make more noise (not a fan) and not necessarily more HP.

Now if you have gone up to a full stand alone MOTEC ECU, Garrett G30-900, with dual fuel pumps with secondary fuel staging, cams, 1500CC injectors and a 4" stainless exhaust, the CAI will make a difference to your numbers.

If you are running your truck on the street everyday keep the dollars in your pocket. If you want performance find a good tuner and invest in a Custom Engine Tune for your vehicle. IMHO The best return on investment.
 
OP
OP
billwinkle

billwinkle

Well-Known Member
First Name
Bill
Joined
Jun 11, 2021
Threads
10
Messages
71
Reaction score
188
Location
North Carolina
Vehicle(s)
2021 Ford Ranger XLT 4X4 super cab
Occupation
Retired
Just got back from a weekend run to Charlotte to see the Nascar hall of fame. On the way back ran 173 miles averaging 75 miles per. I show 22.6 miles to the gallon. And that is thru quite a bit of elevation changes. Truck ran great, no shift problems, did not even feel any turbo lag. I found the only time I could get it to backfire was to load up to WOT and immediately let off the throttle. I am thinking that I am loading up the intake with quite a bit of fuel and not giving the engine time to properly burn it off. If I would load up WOT and run for several seconds (like passing) not backfire.
Thank you everyone for some great info and conversation, I learned quite a bit. I may send this box back and go back to stock. Or maybe the Mishimoto, who knows. Maybe the Fox 2.0 setup, as I have a Leer shell coming in in a few weeks. Or maybe a intercooler, or ???????????
Cheers,
 

P. A. Schilke

Well-Known Member
First Name
Phil
Joined
Apr 3, 2019
Threads
141
Messages
7,012
Reaction score
36,167
Location
GV Arizona
Vehicle(s)
2019 Ranger FX4 Lariat 4x4, 2020 Lincoln Nautilus, 2005 Alfa Motorhome
Occupation
Engineer Retired
Vehicle Showcase
1
I am thinking that I am loading up the intake with quite a bit of fuel and not giving the engine time to properly burn it off. I
Hi Bill,

Direct injection into the cylinder..no fuel in the intake...

Best,
Phil Schilke
Ranger Vehicle Engineering
Ford Motor Co. Retired
 
OP
OP
billwinkle

billwinkle

Well-Known Member
First Name
Bill
Joined
Jun 11, 2021
Threads
10
Messages
71
Reaction score
188
Location
North Carolina
Vehicle(s)
2021 Ford Ranger XLT 4X4 super cab
Occupation
Retired
Hi Bill,

Direct injection into the cylinder..no fuel in the intake...

Best,
Phil Schilke
Ranger Vehicle Engineering
Ford Motor Co. Retired
Stupid me I knew that. I shouldn't type out thoughts when tired.
 

D Fresh

Banned
Banned
First Name
Doug
Joined
Dec 10, 2020
Threads
20
Messages
6,282
Reaction score
13,543
Location
Colorado
Vehicle(s)
'20 Lariat FX4, '17 FiST, '16 CX-5, '95 YJ
Occupation
Milkman
If it's happening when you let off of full throttle it's afterfire. You're tune is probably a little rich. Better than being a little lean.

And our trucks, stock for stock, are NOT faster than a WRX or STi to 60.
 
  • Like
Reactions: Doc
OP
OP
billwinkle

billwinkle

Well-Known Member
First Name
Bill
Joined
Jun 11, 2021
Threads
10
Messages
71
Reaction score
188
Location
North Carolina
Vehicle(s)
2021 Ford Ranger XLT 4X4 super cab
Occupation
Retired
If it's happening when you let off of full throttle it's afterfire. You're tune is probably a little rich. Better than being a little lean.

And our trucks, stock for stock, are NOT faster than a WRX or STi to 60.
That last part was just a little humor. I've driven subis from Stock to actual X-game racers (Crawford performance built). And they are fast little beasts.
 
Last edited:

D Fresh

Banned
Banned
First Name
Doug
Joined
Dec 10, 2020
Threads
20
Messages
6,282
Reaction score
13,543
Location
Colorado
Vehicle(s)
'20 Lariat FX4, '17 FiST, '16 CX-5, '95 YJ
Occupation
Milkman
That last part was just a little humor. I've driven subis from Stockton actual X-game racers. And they are fast little beasts.
You should be used to afterfire then. My blobeye afterfired some with just a catback let alone when I was done with it.


Funny thing is nobody else questioned it. Folks around here really think these trucks are fast. They are fast trucks, but they aren't fast.
Sponsored

 
 



Top