Interesting Video on Direct vs. Port Injection
 

I wonder how Honda avoids having the intake valves gummed up with crap like other DI equipped cars from Germany. Toyota and GM use both PFI and DI in their engines, which helps both from efficiency and as a way to keep intake valves free from deposits. As far as I can tell the L15 and K20C both run strictly off DI.

Here's an alternate view from everyone's favorite profane Aussie car expert:


-- Chuck

Looks like my Civic turbo motor may be recalled due to fuel dilution issues, just like every other DI turbo out there since the Mazdaspeed3 came on the market years ago. Seems like the combination of a DI turbo and modern trannies that keep rpms low (for fuel economy gains) are prone to low speed pre-ignition. Running rich to prevent LSPI and short distance driving typical of most city driving exacerbates the fuel dilution issue. Seems like Honda had to follow the crowd just to keep up with fuel economy pressures.

yeah, the DI engines just aren't perfected yet- sure, better mileages are being realized, but at what cost for the owner who is out of warranty. Toyota provides a port injector in addition to the DI's to keep the valves cleaner as mentioned above. I've been keeping my b16A EM1 as I just can't trust where a DI engine will be 10, 15, 20 years from now.

What are the manufacturers saying- is anyone providing a service interval for them, or are they just sticking their heads in the sand hoping the cars make it out of warranty without major pay outs? I'd be furious if my new DI engine was about to be a very expensive paper weight.

darcy

Word is that Honda will be reprogramming their pcm's as part of the impending recall, and offering a 6 year unlimited mileage warranty extension. I'll take the warranty extension, and with it being unlimited mileage it kind of shows that Honda is confident the current issues are not affecting engine wear. While I've seen some used oil samples with higher than average fuel dilution on the 1.5 turbos, it wasn't accompanied by excessive wear of engine parts. Still not the best situation.

This was posted in one of the responses:

C&D had a Raptor get a lot slower after 40k miles. Makes me wonder...

I just installed a JLT catch can on my Ford 3.5 EcoBoost in my 2017 Expedition which has direct-only injection. Hardest parts of the job are getting to the engine with out a scaffold and reattaching the engine modesty cover. If you have this engine in one of your other cars note the JLT kit has all quick connect hoses. 10 minute job. Can't see any harm. Will check it in a couple thousand miles.

-- Chuck