OLEJOE
Well-Known Member
Probably just one of the many complaints they are going to receive.
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6.7 Engine Air Filter Confusion
- Thread starter mbarber84
- Start date
OLEJOE
Well-Known Member
I think (can’t prove it yet) that the biggest problem with the air filters is the forced air intake. I think it would work fine if it got a consistent amount of air forced into it but the amount of air hitting the truck at highway speeds varies greatly when passing or being passed or following other vehicles. I think the turbulents in the air filter box are what is causing the issue. All theories at this point. Also the water induction in the rain with nowhere for the water to go but through the filter and the engine.
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Interested to hear if cleaning the sensors improves anything. I may do this with my truck today as well....trying everything to resolve the regen and poor mpg performance since the dealer doesn't see any issue (no CELs on).
OLEJOE
Well-Known Member
Haven’t driven it much since I did the cleaning but it’s running pretty good.
Jay P
Member
I agree and also think the fact the air intake is between the shutters and the radiator makes it worse.
Highway speeds have nothing to do with anything, no air will pass through the filter unless engine takes it. Engine RPM and boost have everything to do with how much air passes through the filter, not sure about turbulence or moisture in the air though.
OLEJOE
Well-Known Member
At highway speeds when not towing, it only makes 1-3 pounds of boost. The Ram air effect causes intake pressure to fluctuate or flutter in the intake causing the pressure to go up and down. Minutely but enough to effect the MAP sensor. On the older models (before 19) all of the air was sucked into the filter by the turbo. They did have the valve in the air box that would open when it was hot and when in high boost situations but only then. And on those trucks you could run whatever filter that would fit in the filter box that could take the pressure. As I said at the beginning, this is all theoretical until I can figure out how to do it. They also went to a different turbo on the later models.
CdnHO
Well-Known Member
Agree. The internal combustion engine is really just a big air pump. The faster it runs the more air it pumps. Of course the turbo helps the air get in there. You could run at 70 mph and take it out of gear, letting the engine idle. The engine would take very little air at 70 mph. And personally, I think the ram air thing is mostly a marketing gimick when applied to automotive conditions. Flames anyone?
Riddick
Well-Known Member
The key word you pointed out is turbulence and how this impacts the MAF signal. I am by no means saying we have a MAF sensor issue, I am simply expanding on this topic in general. MAF sensors are very sensitive to air flow, this is exactly why engineers developed MAF straighteners and the MAF housing are always straight and smooth. I previously had a Mustang that made 870 at the wheels and the MAF signal was critical for drive ability. Many of the aftermarket intake systems come with a heat shield but this shield has two purposes. The first one is to block heat but more importantly its to prevent the cooling fan from blowing directly on the filter. I had to modify my intake to fit (remove heat shield) due to other aftermarket components and whenever the fan was on my MAF signal was terrible resulting in part throttle/idle issues. Once the filter was isolated from the "fan wash" the MAF signal improved and no more idle or part throttle issues.
The point I'm getting at is the Ram air system can 100% impact the MAF signal quality. I personally don't believe we have a air intake design flaw since the earlier trucks did not experience this. From what I have seen on here is this issue started around the same time another filter was introduced. Whatever the issue is I hope its sorted soon. I feel very fortunate that my issues cleared the moment I swapped back to OEM filters. If I start to experience any issues in the future my truck will go on a weight loss plan and that for sure will correct the issue.
Riddick
Well-Known Member
Ram air when properly used is 100% not a gimmick. I am going to date myself here but 20 years ago I was very big into modifying Hondas and drag racing. Back then we lived pay check to pay check and all available funds went into our cars chasing more power and better ETs. My buddy had a engine swapped CRX we were trying to break into the 13s, keep in mind this is 20 years ago and a Honda going 13s from bolt ons was respectable. He was stuck at 14.2@98 the entire night so we tested the ram air myth. We removed the headlight/air filter and custom fabbed a 2 liter mountain dew bottle into a Ram air horn (like I said we were poor and had to improvise). After some cutting and duct tape we had a perfect ram air intake for the CRX. Car ran multiple 14.0s@101 that night, did not get his 13 that night but the car picked up .2 and 3 mph in the 1/4 mile which is significant. For what its worth the older hondas did not use a MAF sensors so no impact to how the car drove.
I keep getting reoccurring reports that some of our trucks were shipped with the incorrect MAF sensor. Still can’t get any solid evidence of this. Or a document to reference.
Jay P
Member
I disagree with the comment on the air intake. The 19 and newer have those stupid shutters and the air intake is between the shutters and the radiator. Shutters being open vs closed can have a big impact on air into the air cleaner housing. Towing or a heavy load would likely have the shutters open vs light load/shutters closed which could cause hot air to get into air cleaner housing. Shutters closed could also affect the amount of work the turbo does to pull air in since you have less air being forced into the air cleaner. This may also explain why the 19 and newer are sensitive to air filters.
Jay
The intake isn’t behind the shutters.
Jay P
Member
It is on my 21 2500.
It isn't directly behind the shutters, but the top cover does force the airflow intake from the shutters.
It's going to pull what it needs, but there most certainly would be some effect, even if small, from the shutter position.
Jay P
Member
I removed the top 5 shutters on each side and my regen issue went from every 100 to 200 miles to about 400 miles with the same driving style so those things do affect air flow. I didn't want to remove them all since I'm not sure if there isn't any load on the motor/controller (no shutters attached) it would set a code.
On a side note my regens in cold weather are almost all 24hr regens even with some city and empty driving.
We sold our RV and not planning to get another one so I'm not sure how much longer I'm going to put up with the dealer not wanting to complete the 3 open recalls and regen issues on a truck I no longer need.
Jay
OLEJOE
Well-Known Member
You are correct. The air intake is behind the shutters because the shutters are attached to the backside of the grill. So if the shutters close, the intake is sucking air through the radiator backwards with the amount of air these things use. The shutters are supposed to close at highway speeds but does anyone actually know how they are supposed to operate? That by itself would cause wild swings in intake air temperature and temperature varies the density. What’s the easiest way to remove some of those slats?