400hp?

tvfreakazoid

This is a known issue with carbon build up, so why didn't they also add port injection. Makes no sense. Just another expense unfortunately

I'll be in my bunk!

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Mudders milk

takemorepills

I previously owned a 2016 GTI with DI. Only the NA GTIs came with DI, the ROW GTIs had dual DI/PFI, and a few NA guys did swap the PFI stuff onto their GTIs and reprogrammed the ECU to run it. Also took a custom subharness to connect the injectors to the ECU (where on the NA cars the pins were added to the empty connector positions).

The GTIs and many German DI cars had ridiculous carbon buildup. My exhaust always had thick, sticky, black residue on it, and pics of GTIs getting their valves blasted showed huge boogers of carbon buildup at shockingly low miles. Basically, by 30K miles your engine performance would be seriously impacted by carbon buildup.

I did look at Infiniti Q cars carbon buildup threads and pics online, and the pics of the VR30 carbon buildup seem significantly less severe than the German cars were (I saw "were" because I don't follow the latest German cars anymore). Although not ideal, it looks to me that carbon buildup in the VR30 is so much less than what I've seen before, I'd bet you could go quite a while before having a measurable negative impact on engine performance.

I don't understand why Nissan didn't employ some kind of strategy to deal with carbon buildup, it seems irresponsible for any manufacturer to continue using DI that worsens long term maintenance costs. Heck, our $20.7K 2020 Corolla with the 2.0 engine has dual injection D4S on it!

Magic Bus

2 German car household here, GTI & M2. Couldn't keep that carbon build up off the GTI exhaust tips, despite washing the car every week to every other week. The M2, over 4 years in, exhaust tips 0 build up, same cleaning procedure as the GTI. However I've seen other M2's with owners who don't care, have build up on their's, but nowhere near my GTI!