P0299 is an underboost code, which is usually caused by a boost leak. Check your hose connections, and also check your BOV, as the diaphragm may be torn.
There are recent threads on here in regards to P0299 that were fixed by replacing the BOV.

 

This for sure. Diaphragm is common, and i've had this myself, with no code.

 

im not throwing a cel. I honestly just checked the codes and it was in there.
If I clear it while I drive, I get full boost back for a while and when I hold steady
throttle I hold constant boost. Could it still be bov?

 

Takes like 5-10 mins to pull one off and check it.... I forget if it's 6 or 8mm socket. Personally i'd just check it and be sure.

In my case, I had no CEL, and no code. I just happened to check it for performance related issues.

 

im guessing the Diaphragm is the orange part?
View attachment PartImage_20181029_959 (002).pdf

 

Soooo I’m guessing this hole is a bad thing lol

 

Yep, that’s your issue. I had the same thing.


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i was able to get the valve out by itself.
do you guys recommend changing out the whole housing?
i am doing this in a drive way and just laying on my back under the truck.
i was going to remove the big hose below the plastic housing but wasnt sure if i should or not.

 

I was told the valve mounts to the housing and that where the valve mounts up, its not threaded holes. its a plastic pilot hole and the screws used to bolt down the valve actually self tap in.
Im just worried about stripping the plastic then having a huge problem on the highway.

 

Naw just change the valve. That's what mine looked like. Your hole is much bigger though. You should be in for a pleasant surprise when that gets changed.

I've had mine in and out like 3x on that same body. You're good.

 

Thanks!
cant wait to just be able to tow with it again

 

part should be in tomorrow and i will install as soon as i can

 

Well, the new valve came in and i got the adapter just incase.
took out the old blow off valve and was bolting the new one in.
snapped the head off the bolt. i removed the adapter, put the new blow off valve in and put everything back together.
just got back last night from a 1000km trip and the truck ran 100%. i didn't realize how much power i lost with that bad bov.
its peppy and picks up fast now that it is fixed. fuel mileage also has gotten alot better.

Thanks for the help guys.

next project..... timing chain rattle

 

Do you have by any chance the ford part number for it, and where this BOV is located on the truck thanks

 

I would like to know this also.

 

https://parts.ford.com/shop/en/us/adaptor-turbo-to-exhaust-brake-6552709-1

On that page is a diagram. Part # is 9U465 I think. 10 minute job to replace. Don't over torque it, and use a dab of Vasoline or Lithium grease around the seal, not around the diaphragm itself.

 

Hummm... that look pretty diferent from the parts shown above ? Is it me ?

 

Add you vehicle and it shows a diagram. That isn't the part but I couldn't get the part to come up. The actual part goes onto the part in that link.

 

Got it thanks !!!

 

Bump. Came here looking for solutions to code P0229 on a 2016 3.5L ecoboost with 102k miles. The code would come up and clear itself then come up again. The stock boost gauge still showed pressures of 15psi or more. after checking all the fittings I pulled the blow off valve and found a rip same as others. Thanks for the help. Hope others find this useful as well.

 

Thanks, I am having an intermittent P0299 here lately, and usually only when I start out again after stopping for a bit. Guess I'll look at this. I have 131K miles, so likely culprit.

 

The diaphragm was holed on my BOV actuator, so i am replacing with a turbosmart vee port bov.

 

Thanks everyone for this Thread and the helpful posts. My truck has been doing the same thing. Its not pulling a CEL light it just shows cuz I leave the SCT BDX plugged in. I was getting a p0299 and the p1548. Once the p0299 code pops on my programmer I would be in LIMP mode. Basically the truck felt like it were N/A. The LIMP mode only engages if i go WOT and when I left off the boost is gone. If I clear the codes then I have full boost again and man is it Quick. I have tried just about everything and cant keep spending any more money (I have done quite a few suspension mods also). I like to do things right once rather than fix something for a while. Im just gonna get the Turbosmart Vee Port EM BOV and I really hope that fixes my issue.

2014 Limited 4WD
New OEM Motorcraft Plugs gapped .30
New Turbos (Fully Rebuilt by a Reputable Turbo Shop)
SCT BDX Programmer running 93 Perf Tune
Replaced all 3 MAP Sensors (Brand New)
No Boost Leaks or frayed cables or etc

I dont know what else it could be except the BOV from reading this post. I will let you guys know if this fixes my problem, I really hope so cuz this is really getting annoying. And no one wants to drive a truck around in limp mode or baby the truck all the time to avoid going into limp mode.

 

Just saw this on Youtube...

Was most interesting. I have not had this issue myself, but going to keep this around if I can remember if it does pop up on me..

Mitch

 

Thanks man Im watching that right now. Very informative.

 

I had this code very intermittently, but my truck started throwing other codes about the cats, so got that fixed. It was still throwing this code occasionally. I think the unit can get a hole in the diaphragm and also a little sticky to move. mine lasted 130K miles, but has been defective for at least a year or two! I think it gradually failed, I didn't notice the power loss as I don't tow.

 

Hmmmm...I havent even pulled mine off yet and checked it But I have done pretty much everything else that has been suggested from numerous sources. I just said it and ordered the TurboSmart Vee Port EM BOV. I dont tow anything either, but when the truck is in LIMP mode it doesnt matter what you are doing....you can tell 100%. Its literally like driving around with a fully fuctioning Ecoboost that isnt turbocharged....

 

I would have probably been more upset, but I have a radio that can reset the ecm check engine light, and I do it while moving, even thought it says not to. haha

 

Yea I clear mine off also using my programmer. But Im really anxious to see how much Power Im really losing. What does suck though is every time I clear a code, I have to reset certain things that I change. Its not mandatory but its annoying none the less. I like the ambient light a certain color, I like my Stereo system and Subwoofer set a cerain way, my auto running boards, and etc.

 

Just wanted to bring this up from the dead.
I had the P0299 code as well and the very first thing I checked was the blowoff valve. Large hole.

Thanks! Saved me quite a bit in diagnostic fees and a ton of time.
I will be hunting down part # AA5E-9U465-AD ...update - dealer has it in stock for $52. A bit more expensive than the $35 online but hey...it's in stock and I want the truck back up and running.

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Have a 2014 f150 3.5 CEL p0299, I checked out the hoses all seems good no oil leaking anywhere, I replaced BOV still having the same problem.just like the other people are saying I have boost sometimes, so it’s works sometimes, anybody out here can help me please I can’t seem to figure it out.

 

I too am getting a P0299 code on a 2013, Ford F150.
The code is erratic but more of a nuisance. . I pulled of the BOV sensor and sure enough also has a tear.

Going to dealership to get a replacement and hope this fixes my issue.

 

I too am getting a P0299 code on a 2013, Ford F150.
The code is erratic but more of a nuisance. . I pulled of the BOV sensor and sure enough also has a tear.

Going to dealership to get a replacement and hope this fixes my issue.

Welcome to the forum !
The BOV is very easy to replace yourself.

 

I'm having this issue, 2013 EB. Replaced the BOV already, and did a visual inspection of all the hoses, charge pipes, etc, which seem fine from what I can tell. This seems to be a problem once the truck is heat soaked... it'll drive just fine for 30 mins or so, then go into limp mode, pop the code, and drive like complete garbage requiring a heavy foot to get moving.

Anyone have any other suggestions before it goes into the shop? I watched that video of the different things to check, the only thing I cant test are the wastegates but I suppose I could get a positive pressure pump to try that too, just didn't have one on hand.

 

Did you ever get this solved? Mine does the same thing still after replacing the bov.

 

Was passing on the highway and lost power. The check engine came on and truck was much lower on power, felt more like a 3.5 NA.

put the code reader to it and had the P0299 code. Checked all the tubing and was all secure but happened to have a spare boost control valve in my truck (lol long story)

bolts were a pain but probably took 30 mins. Was super careful and felt like I was really close to breaking them putting it back in.

Very large tare that was probably 1/5 the way around. Cleared the code and test fire it didn’t come back. See tomorrow but pretty sure that was it.

 

Question…. Could a tear in the green gasket cause this to be the source of my code? I pulled my BOV off and don’t see a tear in the orange diaphragm but do see that the green seal looks like it is torn.

 

Yes it could, replace it and it probably won’t come back.