Direct Injection, Problems and Solutions | The Fine Print

Most modern vehicles have a new brand of technology inside their motors, GDI or DI. Gasoline Direct Injection is starting to take over and the development has gone forward. Car makers from Ford, Chevy, Honda, Mazda and much more have adopted this technology. We try and explain what it is, why it was implemented including the problems with carbon buildup, misfires and prevention and other solutions.

Index:
00:00 - 00:49 Intro
00:49 - 1:15 Why Direct Injection is Being Pushed
1:15 - 2:18 How Direct Injection Works
2:18 - 3:32 How PFI or Port Fuel Injection Works
3:32- 4:18 How Dual Injection Works, DI and PFI
4:19 - 4:40 Breaking Down The Marketing
4:40 - 6:38 Why DI is Beneficial and Better than PFI
6:38 - 7:40 Problems with DI - GDI
7:40 - 9:18 PCV Blowby and Carbon Buildup
9:20 - 11:18 Intake Valve Examples - Good and Bad
11:18 - 12:52 Why Not Just Use the Old Way? PFI and Lean Burn
12:52 - 14:45 Preventing Problems - Catch Cans
14:45 - 15:50 Prevention - DI Injector Cleaning
15:50 - 17:55 Prevention - Choosing the Right Oil - NOACK
17:55 - 18:55 When Prevention Fails, Carbon Cleanup - Walnut Blasting and Chemical Stripping.
18:55 Final Thoughts

[TheGabe]

Wow, this is better researched and presented than anything you can read in car magazines today! The level of quality in the content of this channel is amazing.

[bigyeetus]

Man I remember when this channel has less than 20k subscribers, and yet even after all the popularity (still not popular enough IMO) the quality content just keeps coming and coming, even though I'm 2 years late on this one

[redbkr]

He missed one of the biggest reasons for DI: the cooling effect from the very-high-pressure gasoline injection allows as much as a full point increase in compression ratio, which translates to both higher power output and better fuel economy. It's the main reason that modern turbocharged engines are able to run 10:1 compresson ratio.

[Kodiak]

Love your solemnly tone of voice. I thought i was getting a lecture on how to live a better less sinful life.

[mjs]

This was the best researched, and best presented, examination of this topic that I have ever seen. Congrats on a job really well done.

[laurenceho]

This is by far the most professionally made video (very nice graphics), not to mention direct and comprehensive. Just a great short and easy-to-understand video. Well done.

[stephanedagenais]

Quick note on blow-by fella - it is travelling INTO the crankcase from cylinder combustion pressure, not back through the intake valves into the intake. Otherwise, you’re right, nasty side effect of DI. Cheers!

[Deceptive]

What an excellent video/production!! Clear, unbiased, honest and no ego, just the facts and leaving it up to us to make a decision. The world needs more people like you!

[buffystclair]

Very well explained video. Retired now but 45 years repairing cars I often find myself explaining maintenance like this to customers. I dont have 20 mins as your video is but your message is spot on. I wish all car owners would be forced to watch your video and not just think your mechanic is “ up selling” all the time but with that being said, there are often franchises that rely on “up sells” . Find and trust a good shop/mechanic

[FG-fkjb]

Absolutely the best explanation of complex things on the entire Youtube! The guy is brilliant with great, I would say kinda 'soothing' way of delivery.

[johnryan]

This is one of the reasons for Toyota's reliability. A bunch of companies just jumped on the DI bandwagon, and then just left it to their customers to deal with the consequences. Toyota waited until they had their dual injection before they started putting it in everything.

Yes, I drive a Toyota. It was the last year of port injection for my model. Every year after that has been dual injection.

[waltergroesbeck]

Was not fully informed of the disadvantages of direct injection when I bought my Audi TTS. At 60.000 miles an independent shop advised me to have the walnut blasting done, the before and after photos were much more dramatic in terms of build up than even your pics, a sharper throttle response was notable. One note, the shop charged $700.00, my audi dealer 
"estimated" the same procedure at $1900.00 to $2100.00. would you comment in the future as to additives that promise to reduce these deposits ? Thanks for an excellent, understandable presentation about a real world problem.

[StngerGuy]

Great video, I have run into this with my own vehicle.

For anyone willing to get dirty and clean their own intake valves I have found that lacquer thinner works fantastic. Definitely don't do it around any kind of flame or spark, disconnect your battery as well. I did this to my 2012 Turbo'd Optima and the whole process took a few hours. I spent maybe $20 vs the $600 it would have cost. I'm an engineer and like to tinker with stuff and I like saving money. If you have a VW, forget it you will need to have a dealer service it because their engines are setup to be impossible for your average Joe to work on.. I still don't know why the car manufacturers don't just use internal catch cans that pipe the clean air to the intake and the oil vapor to a chamber under the oil pan. Use a longer plug that seals off both the oil pan and the chamber. When you change your oil it also drains the chamber of nasty blow by stuff. Simple fix and the catch cans could be made to be 100% effective using or a large amount of baffling. I put stainless steel wool in the bottom of my catch can to help it remove more nasties.

[johng.]

Wow... This should be a mandatory video to be watched by every consumer before they make a purchase. Kudos to you and how you explained this technical subject in layman's terms. Well done Goose!!!

[IndustMachWerksofTX]

I used STP pro series intake cleaner and it cleaned the valves right up. Good stuff, don’t need to remove anything, it just sprays in the intake for about 10 minutes with engine running

[vincoinc]

This is the best explanation on this that I have heard, I never quite understood why we needed carbon cleaning on DI engines and how the catch cans worked. Just everyone spouting off that you need a catch can with no reason or explanation.

[lashlarue]

This was the best communicated, researched, and annotated presentation of a complex topic. Hats off! My favorite car channel on YouTube! 👍

[rander]

Some observations: The blowby gases do not move up past the rings (~7:17), they move from the combustion process down into the cylinder and into the crankcase. They are then routed back into the intake via a positive crankcase ventilation (PCV) valve. This has been done since the 1960s (I believe). Before that, it was routed directly into the atmosphere out of the bottom of the engine through what was known as a breather tube. Watch an old movie and notice the dark area in the center of highway lanes. That is a big long streak from all the breather tubes from all the old cars as they passed by where oil dripped out. Back to now, sludge does indeed build up on the back of intake valves (not on exhaust valves) for two reasons. The fuel injectors in GDI equipped vehicles do not spray fuel on them as stated and many engines now are smaller and work harder with higher cylinder pressures thereby creating more of these blowby gases than engines of the past. Well, is this a problem, the buildup on the back of the intake valves? Maybe and maybe not. Don't let videos like this say it's always a problem because it most certainly is not. Skipping ahead, the PVC system is most definitely not under vacuum as stated in the video. There is positive pressure in there not a vacuum. Only in turbocharged or supercharged applications are there pressures greater in the intake than in the crankcase and then only when boost conditions exist which are brief and infrequent. Therefore, having an oil that has low volatility in a vacuum is worthless. In summary, this issue is way overblown. Only under rare circumstances do you need a catchcan. GDI technology allows manufacturers produce powerful, clean burning engines. If you run your engine hard and have 300k km or 200k mi on it, you may want to consider cleaning the intake valves but not before. Don't buy into these scare stories. I have a GM 2.0L turbo engine with GDI. GM recommends to not clean the intake valves on my engine. GM designed it, they've tested it, they know what they're talking about. Otherwise a good video.

[LORENSSIOK]

The quality and professionalism in this video is top noch. It's a pleasure to watch and learn.

[JoshuaJDarcy]

Amigo you are a gem! I have owned a 2006 Lexus GS300 GDI for a couple years and did not do my homework on it. I have done nothing but struggle with doing doordash full time and blowing through two quarts of oil a week no leaks keeping the combustion Chamber clean as I can dumping two cans of seafoam spray in it a month and I know I can't keep doing that but I just want to say this was an amazing presentation on very very important subject matter. And as you mentioned, i don't blame the engineers and car producers because you know the regulations that they have to keep up with and balance that with the customer satisfaction as he said so it was just a failed experiment and wow I didn't know what to do with this car I love my car and I keep my cars until the wheels fall off. And thanks to you I'm going to be able to keep mine until the wheels do fall off with some hope at the end of the GDI road which is very Bleak right now but thank you again so very much for this informative video you have really really made a difference in my Approach and now my attitude towards confronting this failed but not dead technology