You probably need your fuel injectors cleaned/cleaning interval recommendations

Joined
11 January 2021
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Location
Ontario, Canada
My search didn't seem to yield a thread on fuel injector cleaning. If you're not routinely cleaning your fuel injectors, you probably should. It's not mentioned on the service schedule, so when should we? Searching online yields suggestions from yearly/12,000 miles to up to 90,000 miles. I wound up sending mine for cleaning by RC after an OBD misfire code alerted me to a fouled plug, but the fouling was probably caused by dribbling fuel injectors as @drew & @Honcho surmised & the plug still lasted 6 years.
According to RC's analysis, mine were desperately due, so definitely more frequently than every 27 years:
PXL_20230507_012306178-min.jpg
Now that I've had the car out again, what a difference! It seems like at least 10-15% more power, which might make sense since one cylinder was down 33% and another almost 50%. So if your NSX doesn't seem as spritely as you remember, this could be a great investment of $174.
One thing to note: Honda recommends replacing the o-rings and the upper and lower seal rings. Don't buy them separately, as RC includes new ones with the cleaning, + the little strainer on the top of the injectors. Witchhunter is cheaper, but I don't know if they replace all the consumables; they didn't answer my emails. Thankfully I had bought the consumables from amayama, so I only wasted $50, as opposed to the Canadian dealership prices.
I think I'll be doing this every 10 years (~30,000 km) from here on but that's a guess.
 
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Tim, that 161 cc is the worst I've EVER seen on a NSX injector report! No wonder you were having misfire issues!

10yr/30,000km is probably a good metric, though in 10 years we may all be running on e-fuels, which burn much, much cleaner than petrol-based, which is full of sulfur and varnish- the stuff that gums up injectors. It's a brave new world...
 
That's the amazing thing, how well it ran for so long building up to that, slowly fouling the spark plug, and that it ran fine after I changed the plug. If it wasn't for you (& other Primers) tipping me to the fuel injectors, I'd never have known & just kept changing plugs every 6 years. Thanks Prime!
 
I don't know if your slow starting would be from clogged/dripping injectors but it's a pretty easy fix.
I pulled mine myself & sent them down to RC in California during the winter. I know it's a pain getting stuff shipped to Canada without crazy brokerage fees, so they sent them back to me on vacation in February.
Fairly easy DIY. The service manual outlines removing the injectors fairly well, although I found it very difficult to remove the electrical connectors prior to removing the injectors because it's almost impossible to get a small flathead in there. Much easier to pull each fuel rail and the injectors and then unplug the electrical connectors, which are a bit of a challenge to unplug:
Once the injectors are out, send them to RC. They will clean them and send them back. From Canada, it could be a few weeks, so I'd do it over the winter. Or you could overnight them both ways, probably not that much more $ & do it in a week, say if you're away on vacation or so. RC replaces the o-rings, cushion and seal rings, and the little fuel strainer at the top, so you don't have to order that. They turned mine around in 48 hours.
When you reinsert the injectors, be sure to follow the SM & insert all 3 injectors into each fuel rail and then insert en bloc in the manifold. Also, be sure to use a torque wrench on the fuel rail and replace the crush washers if so equipped. Later models have o-rings for the fuel rail that shouldn't need replacement.
If you want to get someone to do it in Toronto, call Rob at 9054836247. If he doesn't do it, he will know who to go to.
 
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I don't know if your slow starting would be from clogged/dripping injectors but it's a pretty easy fix.
I pulled mine myself & sent them down to RC in California during the winter. I know it's a pain getting stuff shipped to Canada without crazy brokerage fees, so they sent them back to me on vacation in February.
Fairly easy DIY. The service manual outlines removing the injectors fairly well, although I found it very difficult to remove the electrical connectors prior to removing the injectors because it's almost impossible to get a small flathead in there. Much easier to pull each fuel rail and the injectors and then remove the electrical connectors, which are a bit of a challenge to remove:
Once the injectors are out, send them to RC. They will clean them and send them back. From Canada, it could be a few weeks, so I'd do it over the winter. Or you could overnight them both ways, probably not that much more $ & do it in a week, say if you're away on vacation or so. RC replaces the o-rings, cushion and seal rings, and the little fuel strainer at the top, so you don't have to order them all locally.
When you reinsert the injectors, be sure to follow the SM & insert all 3 injectors into each fuel rail and then insert that en bloc in the manifold. Also, be sure to use a torque wrench on the fuel rail and replace the crush washers if so equipped. Later models have o-rings for the fuel rail that shouldn't need replacement.
If you want to get someone to do it in Toronto, call Rob at 9054836247. If he doesn't do it, he will know who to go to.
 
tim,
thank you for the advice and referral.
am entering the post honeymoon stage ; 2018 for the 91/RI/AT and 2020 for the 02/SS/O/AT low milers
and my long term mechanic retired. a l don't like changing my dentist, barber, or mechanic so a little freaked out about handing the cars to anyone
they are so easy to dent/ding/scratch + any other risks in my hands as it is
i am living north of Barrie since moving from Tdot 2 years ago.
do not see many X's here.
but the roads in Tdot are not even fun to drive X's on.
enjoy
thanks
 
Completing the loop, I've now made a video for changing/cleaning your injectors.

 
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