New Vehicle with DI - Any Tips?

Status
Not open for further replies.
Joined
Dec 18, 2007
Messages
579
Location
Madison, Wisconsin
I retired my trusty Nissan Frontier earlier this year for a '17 Nissan Titan with the 5.6 gas engine. This is my first experience with a DI engine, so I'm looking for any advice people might have. It specs 0w20 oil, but I could have sworn I read somewhere in the manual where 5w30 was "acceptable".

I ran my Frontier 200K miles on 7.5K OCIs with PP. It worked well based on the UOA's I had, but....the Titan has a 100,000 mile warranty, and a 5K specified OCI. I'm going to follow that OCI just to make sure I'm covered from a warranty perspective. At this point, I was just planning on buying whatever 0w20 was on sale and rolling with it. I'd assume with the 5K interval, that synthetic blends would be fine if I can't score a rebate on full synthetic? I've taken advantage of the Mobil 1 rebates to pick up my first oil change, so I'm set there.

I buy Top Tier fuel pretty much exclusively. Kwik Trip, Costco, and Cenex primarily.

I'd considered running Techron in advance of every OCI, just to try and keep the valves cleaned up. Any thoughts on that?

Any other general advice to avoid any DI associated problems? Tips? Things to watch for? I really like the truck so far, hoping to keep it to 200K like the Frontier if all goes well.
 
Last edited:
Only advantage techron will give you is maintaining a proper spray pattern from your injectors to keep the fuel burning clean. Almost none of it, if any will ever see the back of a valve. Using low noack oil may help and avoiding short trips are just about all you can do. Deposits will form no matter what but many say a half hour or so once a week at 3k+ rpm will help cook a lot of it off
 
Keep an eye on the oil dipstick.
Definitely keep the OCI down to 5k miles...even after warranty is up.
See if you can put a catch can on it...check with the dealer about any warranty issues over the catch can.

Check to see how easy it is to remove the intake manifold to clean the intake valves.
You should not have to worry about cleaning (manually) the intake valves for at least 30k or 40k miles.
Oil consumption, if it ever happens, probably won't start for another few thousand miles and can start at anytime after that.
 
7.5k changes for the Frontier? Hmm I've been doing 5k. Would love to see some of your UOAs!

For the DI, like others have said regular oil changes, and if possible a catch can. Catch can won't prevent the problem entirely, but should certainly help. From my research it also seems that DI engines that are "run" on an a regular basis fair better. By "run" I mean pushed a bit. It may be tough to stress a 5.6L without towing or hauling something, but some nice on-ramp runs after is warmed up may help.

The manual for my GTI actually states to run the car on the highway in a lower gear at higher RPM every so many miles or months. I don't do that as it seems like extra wear on other components. But I get the motor going on occasion.
 
There are DI engines and there are DI engines. Some are problems, some are not. Don’t know where your Nissan V8 sits on that spectrum (I know where Honda does, but that’s another story).

The two issues you are likely aware of are intake valve deposits and fuel dilution.

The intake valve deposit issue is generally overblown in my opinion, and is based on the experience of early adopters a decade ago. You just don’t hear many current reports of intake valve issues as OEMs have addressed the problem in several ways. And I’m dubious about the value of a catch-can: a lot of OEMs have designed a catch-can like separator into the engine design. At least see if you Nissan has such a device before adding one.

Fuel dilution is surely a problem with some DI engines. Keep an eye on the dipstick, especially for increasing sump levels. After break-in have a UOA performed by a lab that uses gas chromotography, like Polaris. If dilution isn’t an issue go with the recommended fuel and OCI requirements. If it is an issue, shorten the OCI and/or go to 93/91octane fuel if that isn’t already required.

Use a high-quality synthetic in the highest recommended viscosity and top-tier fuel. And a periodic Techron treatment is a good idea for any vehicle.

Hope it’s an uneventful ownership experience.
 
Originally Posted By: HemiHawk
7.5k changes for the Frontier? Hmm I've been doing 5k. Would love to see some of your UOAs!



Here's my last UOA thread.

Link
 
Last edited by a moderator:
Originally Posted By: Eddie
Enjoy your new ride and don't manufacture possible problems by over thinking. Ed


Thanks! And I think that's great advice.
smile.gif
 
Originally Posted By: Danh
If it is an issue, shorten the OCI and/or go to 93/91octane fuel if that isn’t already required.


What benefits will the higher octane fuel provide? I guess what I'm really asking is how does that prevent fuel dilution?

I will say I tried a couple tanks of 93 (regular is recommended), just to see if I noticed any MPG or other differences. I THINK (and this is subjective butt dyno speak here) that the 7 speed transmission seems to be making better choices for gears with the higher octane. Again, all this is subjective but it just feels crisper to drive. There's been less "wow, it feels like it shifted up too early"
 
Last edited:
Originally Posted By: TWG1572
Originally Posted By: Eddie
Enjoy your new ride and don't manufacture possible problems by over thinking. Ed


Thanks! And I think that's great advice.
smile.gif



I also agree with Eddie. I have never seen a problem with a DI engine.
 
Originally Posted By: Eddie
Enjoy your new ride and don't manufacture possible problems by over thinking. Ed


Exactly! I've had 3 cars with DI motors-two of which were turbocharged-and have experienced no issues with any of them. My first, a 2007 Mazdaspeed 3 was running just fine when I traded it at 158,000 miles- and UOAs indicated that a 7k-8k OCI was conservative.
 
Originally Posted By: TWG1572
Originally Posted By: Danh
If it is an issue, shorten the OCI and/or go to 93/91octane fuel if that isn’t already required.


What benefits will the higher octane fuel provide? I guess what I'm really asking is how does that prevent fuel dilution?

I will say I tried a couple tanks of 93 (regular is recommended), just to see if I noticed any MPG or other differences. I THINK (and this is subjective butt dyno speak here) that the 7 speed transmission seems to be making better choices for gears with the higher octane. Again, all this is subjective but it just feels crisper to drive. There's been less "wow, it feels like it shifted up too early"


It reduces fuel dilution during highway driving in my DI Honda and others here have had similar experiences. We think some DI engines now respond to spark knock by richening the fuel air mixture instead of retarding timing. With low highway revs common these days, spark knock may be common. So, less richening, less fuel dilution. But ymmv.
 
Top tier fuel already has plenty of detergents in it. Not sure if adding more would really do much. I remember that was a topic on Car Talk some years ago and Tom and Ray told a caller that adding extra detergents to a gasoline that already has enough would not be of any noticeable benefit. Basically more is not always better. Before top teir gas back in the 60's and 70's my Dad liked to run a tank of premium every summer and winter through his vehicles. No proof that it helped or hurt but he swore by it.
 
My advice is to not buy a vehicle with a DI engine. It is the main reason I just bought a new F-150 instead of a new Silverado. The F150s, starting in 2018, are dual injected so you still get some fuel over the valves and the Silverado Ecotec3 engines are just DI. If you can use 5W-30 instead of 0W-20 do it. The DI will cause fuel dilution and that combined with a light weight oil won't help.
 
Originally Posted By: Eddie
Enjoy your new ride and don't manufacture possible problems by over thinking. Ed


+1
 
I'm installing a catch can on my new Impala 3.6 DI. Simple to install and not expensive. I'll see what it 'catches'. Whether or not deposits on the intake valves would get so bad that it would affect performance, who knows, and probably not until high mileage. But I like the idea of keeping the intake clean(er). I've ordered a spare pcv line (about $20) in case I have to take the car in for warranty (15 mins to switch it back).
 
We just gave our 09 Acadia to my stepson. We had no problems with D.I. And that was the first year the Acadia had it. Your plan is good. I did 5k OCI and Techron occasionally. Used top tier most of the time.
 
Originally Posted By: Alfred_B
Originally Posted By: Eddie
Enjoy your new ride and don't manufacture possible problems by over thinking. Ed


+1



+ 100

Please know that on here there will be problems with DI cars even when there is no problem, walnut blasting needed when someone has 165K miles on a DI car where there's no need for it, views that indicate DI is a monolithic block of technology and all DI applications are the same, ( VW/Audi circa 2007 same as Asian makes circa 2017 ), a desire to never buy one but also no experience with or interest in DI... yet are authorities on problems you'll experience.

I say use top Tier gas, change your oil every 5-6K miles, use a fuel system cleaner ( whether it washes the backsides of the valves or not ) as its a "system"...and chances are you'll come out alright. I have a five year old DI vehicle with no issues and I'd safely say that I'm more the norm than any kind of outlier.
 
I've had four DI vehicles so far (three turbo, one NA) and have had no issues looking after them according to their respective manuals.

Then again, I'm not the sort of guy who says, "Hey, I should have a look at the backside of the intake valves on this engine that otherwise seems to be operating properly!", either.
 
Last edited:
Status
Not open for further replies.
Back
Top