Hey guys. I have a 15 EX 6-speed, and lately I've been having a series of dash lights come on (flashing to steady TPMS, CEL, VSA, steering malfunction), and even though the lights were off when I took my car to the dealer (naturally), they were able to pull a code for the injectors eventually. Seeing that, they weren't certain, since the car drove fine still, but they basically told me I could keep driving as is, start using premium gas and see if that was the issue, or drop nearly a grand to replace the injectors that may or may not be the issue.
Fast forward to a week later, the lights still come and go in the same pattern (every few restarts, they go away), but I do notice a misfire every once in a while under heavy throttle in higher gears between 1500 and 3000 rpm. The only reason I want this issue fixed is because of the glaring lights (I drive Uber, so it worries some passengers) and the steering gets super light and twitchy, but then doesn't return to center on it's own.
My thing is this: would it be worth seeing if Seafoam will do anything? I know other people have this issue, but mine has 75,000 miles on it, and I've heard that direct injection engines have higher carbon deposits than port injection. Good idea, or no?

 

You could try it, but doubtful it'll change anything

 

You didn't provide the code, but a Seafoam (or BK44) treatment couldn't hurt regards the DI intake valves.

On older Fits the valves drift out of adjustment (exhausts) and the coils are prone to fail. You have 75K miles but you might also have extended idle time so the running time is more...so perhaps you should look at maintenance items that come up at 110K miles.

 

They didn't give me a code officially. Gonna run to a car parts store and have them pull the code for me. And I'll look into the maintenance items.

 

Just kidding, they did find a code. P0171, Fuel System Too Lean. Basically they said bad gas, but if the code comes back when I use premium, I will need new injectors.

 

Bad gas isn't regular versus premium. Bad gas is dirty, contaminated, etc.

It might help to get the injectors professionally cleaned, but I doubt that Seafoam would help at all.

 

Premium fuel isn't premium. It has a higher octane rating which simply means it is more difficult to ignite. Its only purpose is to be used in high compression engines. High compression engines create more heat in the combustion chamber during compression and fuels with lower octane ratings will ignite prior to ignition. This is called pre-ignition, detonation or pinging.

They only call it premium fuel to make you think it's better so you'll pay more money for it.

Since your Honda does not have a high compression engine, it's a waste of money and will do nothing. You should also look for another dealer or tech as the one who told you this clearly has no idea what they're talking about.

 

I don't know what your definition of "high compression engine" is, but to me the GK5's 1:13 is pretty high already. Although the User Manual clearly states to use regular gas.

 

I agree 100%

You could try a double dose of fuel injector / carb cleaner in your next full tank of gas. Drive it until the tank is near empty before refilling.

 

Here is the list of possible items causing P0171 in a Honda.

P0171 HONDA Fuel Injection System Too Lean Bank 1


Possible causes - Intake air leaks - Faulty front heated oxygen sensor - Ignition misfiring - Faulty fuel injectors - Exhaust gas leaks - Incorrect fuel pressure - Lack of fuel - Faulty Mass Air Flow (MAF) sensor - Incorrect Positive Crankcase Ventilation (PCV) hose connection

Read more: P0171 HONDA Fuel Injection System Too Lean Bank 1

Possible causes - Intake air leaks - Faulty front heated oxygen sensor - Ignition misfiring - Faulty fuel injectors - Exhaust gas leaks - Incorrect fuel pressure - Lack of fuel - Faulty Mass Air Flow (MAF) sensor - Incorrect Positive Crankcase Ventilation (PCV) hose connection

Read more: P0171 HONDA Fuel Injection System Too Lean Bank 1
- Intake air leaks - Faulty front heated oxygen sensor - Ignition misfiring - Faulty fuel injectors - Exhaust gas leaks - Incorrect fuel pressure - Lack of fuel - Faulty Mass Air Flow (MAF) sensor - Incorrect Positive Crankcase Ventilation (PCV) hose connection

Read more: P0171 HONDA Fuel Injection System Too Lean Bank 1