Bought my '15 6MT EX March of last year. Just hit 10,000 miles. The following morning I turn my car on and almost every warning light is on, steering, engine, tire, etc. Go to AutoZone to run the codes and in the meantime the car seemed to run fine. Codes came back P0304 P0685 ECM and Cylinder 4 misfire. Pretty much worst case scenario.

I take it to the dealer and after a couple hours of diagnosis they don't tell me the specific issue, say they need to order some parts and come back in a few days. When I return I ask specifically what is being done to my vehicle. The advisor finally stops tip toeing around the issue and says I need a new cylinder head. My baby is on day 2 of repair now and I call back for an update. Advisor says there was excessive carbon build up in the valves so they need to clean that and they also have a head gasket on order they will replace. Also says to run premium gas once a month to get additives in my engine. (?)

I'd say I drive my car a bit harder than the average consumer, redlining it a few times a week however it is my baby I always make sure it has a full tank, fresh oil, and the car is warmed up before I beat on it. I made sure to break in the engine properly for the first thousand miles. Only mechanical mod is lowering springs.

I'm extremely disappointed as the biggest selling point for me is Hondas reputation as a reliable brand. For my new car to fail at 10,000 miles is something I don't wish on any Fit owner nor have I found another case like mine for the GK. What actions should I take to make sure this doesn't happen in another 10,000 miles?

Any input is appreciated.

 

Yikes. Side effect of direct injection? Faulty PCV?

It wouldn't be unusual to see this in a high mileage vehicle. But at 10K, something weird is going on.

I can't help but wonder if the redlining + direct injection leads to this situation developing much earlier than we would normally see.

For reference, my GD3 5MT (not a direct injection engine) was still going strong at 147K when it was recently totaled by a red light runner. Didn't burn a drop of oil, was on its 30th oil change, never redlined. But it's a different engine so not an apples-to-apples comparison.

 

Are you using Top Tier gas per the manual? I would think continued use of gas not rated as Top Tier could cause the problem.

I'm at 10K miles and all is well.

 

Well, that's what the warranty is for- Honda didn't think it was going to happen either because they're really good at building these little engines. They probably spent quite a bit of time trying to figure out exactly how it happened, because it shouldn't have happened.

I haven't heard of one of these either, and I doubt you'll see it again. When it's all back together, we'll all be curious to hear what they say happened. Good luck, and I hope this incident (and the way dealer works it) doesn't shake your faith in your car.

 

Carbon buildup is a common issue for DI, regardless of manufacturer.

 

I'm at 23k+ and counting and so far so good.

Could be just random bad luck otherwise we'd be hearing of a lot of other reports. Reminds me of a coworker who had a WRX. He had an engine replacement at 10k. Was told there was a bad batch that went through the factory and he just was unlucky to get one. Full engine swap covered by Subaru.

 

Almost 10k on my ex manual and doing fine. It still feels strong as the day i got it. But i do run premium once a month. Carbon build up is known DI issue, but it could be the L15 is weak engine to redline.

 

if this really was a "major engine failure" as u stated, how did you "take it to the dealer"?

post up picts of ur car and details where u took the car, which dealer, etc.

 

I appreciate your perspective. It's an alternative way of looking at the situation. However, it's probably difficult for the owner to consider at this time. Warranties are welcomed assurances to cover unintended consequences, but I think most consumers prefer to avoid any trouble in the first place.

 

Wow, I have heard a lot of carbon build up after 30k miles in other cars(vw group and bmw). I wonder it the car is not going to last as long as the olders honda.

Also could you give us more info about your car other than ex manual. Like what gasoline, average speed, maintenance schedule.

I hope not to heard about carbon build again.

 

I know of one member, Harry Houdini or something like that with at least 100k miles in a year. Yes one data point, like the OP, but I'm confident the engine could go much longer.

 

Like stated above, this is a direct injection issue, not necessarily a Honda issue. My first suspect wouldn't be Honda, it would be the fuel source. It sounds like your area has shitty gas.

Also, dump a bottle of injector cleaner in the tank every 5-8k miles or so.
I'm hoping for the best. I have two of these cars and they've both been great.

 

Most of the time I fill up on a military base at the same gas station, up to 10% ethanol. Most of the people filling up there drive pretty nice cars that their gov job provides.

I drive mostly city, average speed 40 mph. My driving style is to get up to speed, around 35-40 by shifting quickly at 3-4 thousand RPM. Once there I just cruise for fuel efficiency.

As far as maintenance goes just the scheduled oil changes by dealer. I've rotated the tires every couple thousand miles and regularly make sure im at 35 psi. Car has driven normal entire time from when I got it diagnosed to the dealer and for 2 days after when they wanted me to bring it back.

Full mod list-
18% tint all around including sun visor, 5% sunroof

Replica mugen visors

H&R sport springs

Alpine Type R 12 in subwoofer, Hifonics Zeus amplifier

DragonballZ shift knob

Husky floor mats

 

Idling for extended periods can really do in the DI motors, do you have to sit in traffic a lot?

 

Update- dealer changed cylinder head, head gasket, injectors and injector pipes.

Car is running ROUGH now with a loud engine tick that gets worse as I apply gas. Video to follow in the morning, I'm contacting Honda USA to try and get a new fit or at least my motor replaced. My car was silent before, barely a buzz idling.

 

Coming from the valves, perhaps? Did the dealer mention anything about clearing the carbon buildup from them?

 

They said they cleaned it out. My friend even told me my car is loud idling today, it's bad.

 

Sounds like the valves may be out of adjustment. Back when I had the "lost motion spring" recall done on my '09 Fit, it took the dealer THREE tries to get the valves set right so they didn't rattle and didn't throw error codes.


Take it back!!

 

How the hell can someone ship a car like that?

 

This, why did you accept the car if it were doing that?