Why is the Ford Focus RS Intercooler Blocked Off? 

I don't even plan on owning a focus rs but the sher knowledge that you take time to provide to the public is awesome and (I'm sure I can speak for everyone that watches) I really appreciate you for sharing all the research and findings that you discover!

Thanks for the explanation! It's nice to know the reason behind this black block. I saw quite some car reviewers including Matt Farah just said that you could simply remove it and improve your performance right away.

That was fascinating, you learn something everyday. Thanks

It's great to see a real explanation as to why this is done.

The gen 1 3.5 ecoboost in the f150 has this issue under low throttle conditions as it would collect moisture in the intercooler in humid conditions, then when you stabbed the throttle for say climbing a hill it would ingest all that into the motor at once causing it to stutter and shutter bad (happened twice to me). The biggest problem was how low the intercooler was in the intake chain, it was the lowest part so water would easily collect until it was surged up into the plenum via boost on throttle and or inertia. Ways they dealt with it was blocking off parts of the cooling vanes inside the plastic caps of the intercooler, rendering the effective cooling to be slower or less efficient as stated here. However many found that drilling a weep hole in the bottom of one cap would allow a constant small pressure release that acted as a purge to push condensing water out before it could collect in any capacity, yet not a large enough hole to affect boost pressures at the manifold as the turbos nearly never hit peak load and could over take the loss. (Note that drilling the intercooler will void warranties). Best way to combat this tho, was a mild tune. It added boost more frequently in the lower rpms, which pulled through condensate before it could gather in pools. Never had a repeat after I put in a unichip. Pulled the chip after I sold the truck tho.

You say 'for now I'm Brett Middleton' - I was just wondering who you will be later on?

Hi thanks for the explanations, my rs has Revo stage 2 unit, with a huge intercooler, all silicone pipes, a mounting hard pipe, mounting cold air kit and k&n filter and I use magigas ak5 octane booster and royal purple ice mix for keeping the temp low, the car is now a real beast.

I do love the explanation, and it totally makes sense! The solution is equally brilliant; and simple. :-) Just to add complexity, it would be fun to add a variable air dam in front of that intercooler in place of the blanking panel. It can be easily varied based on information gathered by other systems. Just knowing the relative humidity outside and the dew point would be helpful in determining whether or not the intercooler needs to be blocked at all. At high altitudes, it would likely never need to be blocked at all; as the dew point can be below freezing even if the relative humidity is 90%+ on a 35°C day. However, at low altitudes, ot hot days, it'd likely need to be blocked all the time, as the dew point can be higher than 35°C, on a hot day.

So you can take it to the shop and they say “ok I found the problem, apparently you have a blocked cooler, that’ll run you around $1100, but I’ll do it for $1050”

That was well worth watching! Thanks for such a information filled and well presented video!

Your current 875 likes, I suspect, are all from currently confused RS owners who indeed have suffered this misfire issue, good video that clearly explains what the problem is, big thumbs up for being clear and concise unlike your local Ford dealership

Is that cheap piece of rubber glued to the intercooler the same material they used for the head gasket?

That's honestly something I never considered, but now that you've mentioned it that makes perfect sense.

great video, I wonder why my air filters never damp? if there's enough moisture to condense and form droplets surely my paper filter should be wringing wet after half an hours drive in the fog? I've never seen water corrosion on any intake path even after using steel exhaust tubing for intake piping a few times. the outside goes brown but the inside of the pipes never rusted?

Awesome video! very informative and educating! keep up the good work guys!

Fantastic informative and concise, great job👌🏻

Very interesting and great explanation here on a problem I'm sure most people would never think of

Awesome video mate! So being in Australia, would you recommend keeping the blanking plate or will removing it be safe here in Sydney?

Really interesting and really well explained! Thanks!

Quality info/channel you have here. Subscribed.

VW TDIs had this same problem... they'd collect so much water in the winter time, it would turn into a slug of ice that would either starve the engine of air while driving, or melt when the car was parked and hydrolock the motor when it was restarted. They did a service action to fit a new intercooler with a diverter valve which closes off ~40% of the fins. It gets activated at some temprature near freezing.

Thanks for the video, very well explained.

Not a Focus RS owner, but really interesting video. Great explanation.

Wow! Very informative, Subscribed!

So much info. Holy crap. Good vid!!!

Top video as always man.

Great video 😁 always helpful

Great presentation, you have earn't a sub!

Great video, thanks for taking the time of making it :D

This is food for thought. I live in Louisiana, USA, and it gets very humid here in summer. Now I dont have a Ford or even a factory turbo car (I building a 93 accord), but I wonder if there is a way to accurately determine if the intercooler I'm using is too much and causing condensation?

This is some awesome info.

Excellent video mate 👍 condensation... who would of thunk it

Awesome information, good on ya 😁👍

So if I had this car, since I live in a climate where the humidity is basically non existent, I live in a desert in Southern California, USA, but I'd be able to removed that block off plate (don't know what else to call that floppy piece of rubber/plastic whatever it is lol) and then get a custom tune and take full advantage of what Ford originally intended until they found out about the Humidity and condensation problems? Am I interpreting you correctly? Sounds awesome too since you said cooler inlet means, the ability to advance timing, and that means more torque, and I like the idea of that since it's a 4 cylinder and the more torque the more it feels like a bigger engine.

Awesome vid thank you

Finally someone that makes me feel like the saying, "learn something new every day" actually applies to their video, and isn't just recycling someone else's crap for the millionth time.

I know nothing bout cars nor really care about them. But this was a superb vid and extremely informative. the star was knowledgeable and well spoken. Thumbs up.

Great information my friend!

What are your thoughts on air to water inter coolers, and is it possible to make the inlet air too cold?

Great video mate

Same intercooler as on F150 and Explorer. Some people had water condesation on a long drive in humid rainy condition (early f150 ecoboost ) so they fix the issue with sticker. I removed my sticker on Explorer and make sure I hit full boost every time I drive - to clean out any moisture in the intercooler. Small amount of moisture will clean carbon, large amount will cause misfire (just like seafoam engine treatment ). I live in Michigan, humid climate, never had issues with sticker removed, but I do not baby the car...sticker is there for old people who drive light.

Great video!

Very informative thanks 🙏 sir

Did yoi dyno that RS before and after removing that block off plate?

Is there a good alternate for areas with high humidity?

Good video!

Once again very informative keep up the good work

Can some type of diffuser be installed on cool side to turn the water droplets back into a mist form and simmulate a water/methanol system? Or would it have to be pressurized like a water/methanol system?

It would be interesting to see if there’s any difference in power from removing that piece blocking the intercooler. I’d like to see someone test it on a dyno.

I live in Michigan, I also removed the rubber flap that Ford glued on the intercooler and in the winter time I would make about 8 psi less boost than summer time

Super interesting 👌🏼

Perfectly explained.

Just curiuos why then so they make intercoolers as big as a 34 in tv where you have to remove all but the bumper skin?

Soo.. if you wanted a bigger cooler and had moisture to deal with.. is there another solution?

Thanks for the video! Is there any benefits of upgrading my intercooler in a cold climate country?

Lessons learned from the 1st generation 3.5 Ecoboost F150, we installed block plates over the top 1/4 of the intercooler to raise the temps of the charge air.

Love the thought they put into an intercooler. To bad they didn't do such a good job on the head gasket of the turbo 2.3 . Atleast with the old quad 4 from GM you got 70 miles out of it before it blew. Their are vids up with RS owners with less than 20k miles with the Ford turbo 2.3 that are so bad they warranty the entire drive train. Due to the gasket failing so badly it warped the head and the block deck beyond repair specs. Good video though.

My Ford Explorer 3.5 ecoboost had the same block plate on the intercooler. If I'm not mistaken all Ford intercoolers have them.

Very interesting. So what about all these tuners running around with huge intercoolers in humid areas? Because pretty much during the course of a year it can get humid almost anywhere

In cold areas that water gets Frozen in the cooler and when it melts it can hydrolock the engine. Has happened to passat and some other vw cars.

Is it a problem in Australia? I can understand the problem in snowy areas.

Do our Australian Ford Focus RS's suffer head gasket issues like the US models?

I have up graded my st to shortin the gear shift and its the same bits thats in the trasit and the rs . And a lot of the bits on the st come from volvo . You find it out as you take the car apart .

Hey, this is a lot like one of those Apple design 'Features'..

So, why does this not seem to be a problem on tuner cars modest sized turbo's maxed out with giant FMIC? Is it because with the a setup like that the post compressor air temp is much higher, thus the large FMIC isn't so over kill after all and doesn't cause the problem?

A lot of the Ford F150 with ecoboost engines have intercooler water condensation problems. People drill a little hole in the bottom of the intercooler to drain the water. They might lose a bit of boost, but there are still plenty. The turbo might just need to work a bit harder, or the waste gate don't have to release as much.

Meh, a bit of carbon cleaning isn't that bad :D

Most ford’s with an eco boost engine have a TSB for that issue depending on build date

I don't own a focus rs, but I live in socal and it's almost always 0% humidity, very dry where I live, so i would def take that off

My EVO VIII MR had its shares of quirks, but nothing like this, or the deck issue on some RS models.

I got my own ford corrected .... I sold it and now I am the happiest man

i have a 2014 2.0 turbo ford fusion..i live in califronia.. and the air is very dry most of the year..even in the winter so i removed that cover. a few months ago..maybe some power gain, but to little to feel..i also removed it as it was 7 years on the car.. and could not see the sun thru it..bugs, leaves etc.. so i water gun washed it forward and backwards a few time.. after i could see thru it,, reinstalled.. after that i did notice a power increase .. i shall do this once a year..its pretty easy to take off the front bumper cover

Mighty Car Mods...

This is the first I've ever heard of this issue, must strictly apply to cold weather conditions. People have been upgrading their intercoolers for decades and never have i heard that they work so well that water droplets form. Doesn't this essentially say you can not only not remove this in certain areas of the world but that you cannot even upgrade the FMIC?

Serious question then. An aftermarket inter cooler would have the same problems no? I do live in an extremely humid climate. Are there solutions to this problem that don’t sacrifice performance?

How about just putting a "leak off" check valve kept warm by some part of the intake air or other part of the car, so the water could just seep out? With the air flow in question, any air leakage out would be insignificant. Similar concept to why I leave open very slightly the ball valves on a shop compressed air supply tank and downpipes to bleed off accumulated moisture.

Interesting stuff. :)

Maybe it was an emissions thing i notice a 5 mpg drop when is really cold out

A way to take advantage of the bigger intercooler area, without dropping the inlet temps to the point where condensation would occur, would be to turn the boost up a bit. More compression = more mass flow into the engine, but a higher temperature; more intercooling drops the temperature back down to where you started. This does make the naive assumption that raising the boost pressure doesn't trip the engine into detonation - to do the proper job, you'd have to drop the engine's compression ratio a bit too, which is a lot of work and / or cost.

A bit of water injection should lower the temps, reduce knock and allow increased ignition timing. Not convinced about the trapped condensate.

Is that Matt Farah’s?

will buy the next focus RS once it got a dual clutch

wow good to know

Ford does the same on the F150 ecoboost trucks mine had a black plastic block off plate

As others have said, a tiny weep hole would eliminate water buildup while maintaining maximum cooling.

how much you want to bet it was a leaky head gasket that caused the misfire, and not the intercooler

Would be interesting to see if long-term owners find this blanking plates glue wears after awhile and causes a change in power when the plate falls off

Or they did that as a lil performance gain you can do obviously pretty easy, hidden secrets... like 1g eagle talons having 2 step in their ecu, or the lil ball in r32's that when removed give like 5 psi more

Does Australia have as tough an emissions standards as does California?

Ford had hell with this problem in the first Ecoboost F-150's sold in Florida and S. Texas. People having all kinds of hesitation, stalling and misfire problems. They finally tracked it down to the issue described here. RU-vid search "ecoboost F150 hesitation"

The heat exchangers on air conditioners are WELL bellow ambient thanks to the endothermic reaction caused by evaporating the refrigerant. Intercoolers on turbo cars, besides a refrigerant based system like on the dodge demon, do not yield cold air (unless they're using cold ambient air which is much less likely to be humid). They cool the air down to near ambient temps, but cannot even get to ambient (would require 100% efficiency). I'm not saying you cannot get condensation in the intercooler. The extremely narrow design of this particular one coupled with Ford's insistence on running ecoboost turbos well beyond their efficiency maps (generate a ton of heat) is the problem, as the temperature differential is greater than typical systems and you're running that air over an even smaller surface area.

My B9 Audi A4 had the same deal, a plastic blanking plate clipped around the entry side of the intercooler

How does the water droplets cause misfire?? Spark plugs and injectors are pretty weather proofed. Where is this extra humidity causing a problem in the engine?

I cannot thank you enough.

The real solution is to run smaller gaps on the plugs, and to frequently change the plugs. I have the MKS EcoBoost which had the misfire before I replaced the plugs and gapped them at 028. Factory calls for 035-040. This is a common problem in turbo cars with intercoolers.

Well,Cool thing to learn about,I live in Norway so I'm thinking of ripping it off,but still,it's there for a reason,but then again,if there is any gains why not....

My 2013 fusion 2.0 turbo had this blanket on the intercooler I removed it no issues California

It can happen in just about any region with the right conditions and really no turbo car with intercooler is immune to it to a certain degree... conditions how the water forms, strips off or is ingested will vary. The interesting part here is that it was actually thought through as a possible outcome during development. Think about how many tuners would ever think a larger or more effective intercooler is a bad thing.

What i dont understand is how my m50 turbo with a intercooler 3 times the size of that is not causing condesation in the mountain where i live, very high humidity. When i drive it like a normal car the intercooler is cold to the touch. No issues with condesation. M50b25 forged, fmic 100mmx600x300, gt3076. And to top that off i run wmi also

So the average humidity in my location is 73%. Is that too high to take the blocking plate off?