Intake Valve Carbon check for 3.5 EcoBoost GTDI engine -easy-

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

onanysunday

Member
Joined
Jun 13, 2023
Messages
39
Reaction score
18
Location
Minnesota
Hi,

I posted this in response to another, unrelated thread but thought it would be a good idea for everyone to see and be able to have easier access to. I apologize if this exact method has already been discussed in an earlier thread, I am new here. I have the 2013 FPIS 3.5 EcoBoost. These GTDI engines are notorious, or should I say a "ticking time bomb" for carbon build-up on the backs of the intake valves since they use direct injection and not port injection that sprays a gasoline mist on the backs of these valves which cleans them (like other engines do). Because of this, the state of build-up on the backs of the intake valves at any time is an "unknown" you don't necessarily want to take for granted or have looming over you. It should at least be checked and periodically cleaned (relatively often). If you wait too long or have never done this before and the vehicle has high miles, it's not a bad idea to check. Also, this build-up can happen relatively quick which is why some people install a catch can. Please note Ford does not have an approved method of cleaning these intake valves, will not perform this cleaning service, and recommends replacing parts instead. I imagine some failed attempt at this could void a warranty. So proceed at your own risk, etc.

Long story short, I found that an articulating borescope fits perfectly through the MAP sensor hole directly on top of the intake, allowing you to get a good glimpse of the amount of carbon build-up on back of the intake valves without having to disassemble anything besides the one torx screw holding the sensor in place. I'd say this is highly recommended for these engines and this intake design in particular as it's very easy to do. What this does is that it can help give you an idea of whether or not something like CRC Intake Valve and Turbo cleaner is a good idea (if the build-up is mild) or a bad idea if the build-up is severe in which case intake disassembly and walnut blasting -or manual carbon removal- is a better choice to avoid larger amounts of carbon chunks from accidentally getting into and scoring the combustion chambers or damaging the valves or turbos before the build-up has a chance to be liquified by the cleaner as it is sucked in (and through) the engine. Also, it's not a bad idea to run some Lucas Upper Cylinder lubricant in your gas (and a box fan on high) on a colder day when attempting the spray method to keep the turbo heat in check.
 

Attachments

  • borescope hole for intake carbon check.jpg
    borescope hole for intake carbon check.jpg
    393.2 KB · Views: 59
  • CRC.jpg
    CRC.jpg
    30.4 KB · Views: 46
  • articulating borescope.jpg
    articulating borescope.jpg
    29 KB · Views: 44

onanysunday

Member
Joined
Jun 13, 2023
Messages
39
Reaction score
18
Location
Minnesota
I picked up this car last month for a pretty good price. It has 147k miles and I was pretty concerned it was going to have lots of carbon build-up on the intake valves. Fortunately, it had some recent work done around this area before I purchased it. A new head gasket had been installed and it appeared there was also some intake cleaning done at that point because the build-up wasn't too bad after I checked it with the borescope, but there was still a fair amount of carbon to clean. Glad I checked first instead of going into this blindly.

As always, Lucas UCL was added to the gas tank and I secured a box fan under the hood over the engine compartment using the loop latch on the hood with a bungie cord while securing the base of the fan to the top of the firewall area which really seemed to help keep engine temp in check with the cooling fans only coming on a few times throughout the entire cleaning process. Before the cleaning, I was getting an annyoing check engine light every single time I pushed the car hard that would go away after about 2-3 car trips. While cleaning, I noticed the engine started to smooth out and get a little quieter. It also seemed like it was running faster or rpms were increasing with the gas pedal secured at just the right prm with a brick on the pedal. However, the tach confirmed my rpms were staying constant throughout the entire cleaning process at around 2,000 rpm which was interesting. After spraying the whole bottle, it now accelerates quicker, feels smoother and is a bit more powerful off the line. I would say it now runs noticeably better. As an added benefit, it no longer throws the check engine light at WOT, which is huge and totally unexpected. All in all, it was a great success when combined with the Liqui-Moly Engine Flush I used before the last oil change. I may still install a catch can at some point, but I should be in the clear now with regards to my intake valve carbon build-up as long as I periodically clean the intake valves before they ever have a chance of getting too bad or dangerous to clean using the spray method. I am thinking I will repeat the cleaning every 10k miles or so. One application helps, doesn't clean everything out, and is not as good or thorough as walnut blasting. But for me, it's good enough and I'll probably just administer a second bottle here pretty soon to help clean more of what was missed during the initial application.
 

kryptto

The Best Thing About Cars... ones in my mirror.
Supporting Member
Joined
Mar 24, 2023
Messages
1,382
Reaction score
730
Location
South East, Florida
Hi,

I posted this in response to another, unrelated thread but thought it would be a good idea for everyone to see and be able to have easier access to. I apologize if this exact method has already been discussed in an earlier thread, I am new here. I have the 2013 FPIS 3.5 EcoBoost. These GTDI engines are notorious, or should I say a "ticking time bomb" for carbon build-up on the backs of the intake valves since they use direct injection and not port injection that sprays a gasoline mist on the backs of these valves which cleans them (like other engines do). Because of this, the state of build-up on the backs of the intake valves at any time is an "unknown" you don't necessarily want to take for granted or have looming over you. It should at least be checked and periodically cleaned (relatively often). If you wait too long or have never done this before and the vehicle has high miles, it's not a bad idea to check. Also, this build-up can happen relatively quick which is why some people install a catch can. Please note Ford does not have an approved method of cleaning these intake valves, will not perform this cleaning service, and recommends replacing parts instead. I imagine some failed attempt at this could void a warranty. So proceed at your own risk, etc.

Long story short, I found that an articulating borescope fits perfectly through the MAP sensor hole directly on top of the intake, allowing you to get a good glimpse of the amount of carbon build-up on back of the intake valves without having to disassemble anything besides the one torx screw holding the sensor in place. I'd say this is highly recommended for these engines and this intake design in particular as it's very easy to do. What this does is that it can help give you an idea of whether or not something like CRC Intake Valve and Turbo cleaner is a good idea (if the build-up is mild) or a bad idea if the build-up is severe in which case intake disassembly and walnut blasting -or manual carbon removal- is a better choice to avoid larger amounts of carbon chunks from accidentally getting into and scoring the combustion chambers or damaging the valves or turbos before the build-up has a chance to be liquified by the cleaner as it is sucked in (and through) the engine. Also, it's not a bad idea to run some Lucas Upper Cylinder lubricant in your gas (and a box fan on high) on a colder day when attempting the spray method to keep the turbo heat in check.
Amazon part link for the scope would be great!
 

onanysunday

Member
Joined
Jun 13, 2023
Messages
39
Reaction score
18
Location
Minnesota

kryptto

The Best Thing About Cars... ones in my mirror.
Supporting Member
Joined
Mar 24, 2023
Messages
1,382
Reaction score
730
Location
South East, Florida
@yaycandy any suggestions of where to spray the CRC GDI cleaner if the map sensor is on top of the intake, and past the throttle body, thus in the way of the cleaner which is not suggested? CRC - says run the car - cant imagine what to disconnect to keep the car running, and not throwing all sorts of codes. How is everyone else applying the cleaner, keeping in mind I dont have meth - or some other method to enter the system.
 

yaycandy

Aerospace Engineer
Joined
Jul 2, 2018
Messages
2,451
Reaction score
1,788
Location
Hanover, PA
@yaycandy any suggestions of where to spray the CRC GDI cleaner if the map sensor is on top of the intake, and past the throttle body, thus in the way of the cleaner which is not suggested? CRC - says run the car - cant imagine what to disconnect to keep the car running, and not throwing all sorts of codes. How is everyone else applying the cleaner, keeping in mind I dont have meth - or some other method to enter the system.

Vacuum hose on the factory intake tubing. Will go through turbos and intercooler also. Or just unclip the vacuum line behind the throttle on the left that runs to the brake booster and spray in there. Running higher idle from vacuum leak will help it work better. Or have 2 people with one person holding the throttle about half. You can also remove the front map sensor before the throttle. Dont unplug it but just remove it. Still plugged in, will run fine. Just dont drive around with it removed. I have before but i don’t recommend it. I do pretty stupid stuff.

Disconnecting the brake booster line at the intake manifold will throw a brake light and a message but no codes. They will go away once you plug it back in and restart the car
 
Last edited:

kryptto

The Best Thing About Cars... ones in my mirror.
Supporting Member
Joined
Mar 24, 2023
Messages
1,382
Reaction score
730
Location
South East, Florida
Vacuum hose on the factory intake tubing. Will go through turbos and intercooler also. Or just unclip the vacuum line behind the throttle on the left that runs to the brake booster and spray in there. Running higher idle from vacuum leak will help it work better. Or have 2 people with one person holding the throttle about half. You can also remove the front map sensor before the throttle. Dont unplug it but just remove it. Still plugged in, will run fine. Just dont drive around with it removed. I have before but i don’t recommend it. I do pretty stupid stuff.

Disconnecting the brake booster line at the intake manifold will throw a brake light and a message but no codes. They will go away once you plug it back in and restart the car
Thanks yay! Appreciate the quick response.
 

onanysunday

Member
Joined
Jun 13, 2023
Messages
39
Reaction score
18
Location
Minnesota
I sprayed mine directly through the throat of the throttle body and it actually cleaned all the tiny bits of carbon off the top intake manifold MAP sensor with zero issue. I had "cleaned" that same MAP sensor a week prior with electrical contact cleaner, but it came out waay cleaner after spraying the TB with CRC. It is essentially an epoxy coated ceramic capacitor? and seems to take the additional cleaning quite well. It can also be done as a one-man job when you carefully position a weight on the accelerator pedal at a specified rpm.
 

kryptto

The Best Thing About Cars... ones in my mirror.
Supporting Member
Joined
Mar 24, 2023
Messages
1,382
Reaction score
730
Location
South East, Florida
I sprayed mine directly through the throat of the throttle body and it actually cleaned all the tiny bits of carbon off the top intake manifold MAP sensor with zero issue. I had "cleaned" that same MAP sensor a week prior with electrical contact cleaner, but it came out waay cleaner after spraying the TB with CRC. It is essentially an epoxy coated ceramic capacitor? and seems to take the additional cleaning quite well. It can also be done as a one-man job when you carefully position a weight on the accelerator pedal at a specified rpm.
Excellent notes, thanks!
 
Back
Top