I was chatting with a coworker who told me that all cars need cleaning
of the injectors every 30 to 60k. Heck, I have a 98 Civic and a 2000
Civic and, to me, they run perfectly well with about 100k miles on
Isn't it that if anything goes wrong with the engine (including
clogged injectors), then the mileage will drop? Both cars exhibited a
mileage increase from day zero to up to about 3 years of use, then
stabilized to about 34-36mpg for 50/50 city/highway driving.
So, is it true that sooner or later the servicing will have to include
injector cleaning or is my mate bs-ing?
He's BS'ing. Or just doesn't really know and is guessing.
Mileage drops, starting problems happen, *then* you do something with
the fuel. And even then most "fuel" problems are actually ignition
Keep in mind you need to keep ACCURATE track of mileage over the course
of two years or so in order to see what your car is *really* like. Then
you see if that changes, which alerts you to problems. ACCURATE is the
keyword here! Don't just go by how many miles you get out of a "tank".
Modern fuels contain copious amounts of detergents. Injector problems
will arise if the car sits for extended periods, or is used almost
exclusively for short-hop city driving. Anything other than that and the
detergents will clear off the crud.
Except unusual situations, I always fill the tank up after 320-350
miles and carefully mark the odometer, tripmeter and gas amount.
Therefore, I have the whole mileage picture starting back from when
the odometer was reading single digit figures :-)
not b.s. yes, cleaning can help problems like leaky injectors and to
some degree, excess carbon in egr systems.
detergent content varies by gasoline brand. stick to good brands,
preferably "tier one".
you can also run cleaner through the system yourself for minimal cost.
avoid the "flush" service sold by places like monkey lube.
These cars see only Shell gas (except when not available during longer
trips). Tegger's confirmation that I should see a mileage drop if
something's wrong makes me feel the cars are very OK.
B.t.w., I noticed on this forum that Chevron is touted as being the
best gas in US, mostly because of the Techron additive. Is it so much
better than 76 or Shell? And, what's up with the joker regarding the
gas sold in California being dirty ?!
chevron is ok, but not exceptional imo. it may be "clean", but it
doesn't seem that great on energy content. 76 used to be good, but now
sucks since it was sold to conoco. shell is ok.
in general, california gas sucks. special single state formulation is
ridiculous and inflates prices. 91 octane is the highest available.
In the most sensitive car I've had, a 1984 Nissan 300ZX with manual tranny,
76 was most convenient to me but was terrible for injector cleanliness. When
the clutch started getting tricky (every couple months) I'd put in a tank of
Chevron or Texaco and it would straighten out within a hundred miles or so.
Shell should be as good, as should BP where it is sold (not around here).
Dunno about California.
I'm with 'jim beam' - use of "top tier" gasoline brands eliminates the need
for injector cleaners. Otherwise adding cleaner (or filling up once with top
tier gasoline) about every oil change is a good idea. I've learned from
If your car has an automatic tranny and the weather is mild year 'round you
might never notice the difference. If you have a manual tranny you will
probably first notice the clutch seems to be getting "grabby" coming off the
line, deteriorating over a month or two to the point of being frustrating.
Amazingly, cleaning the injectors seems to fix the clutch! And cold weather
can make starting tougher if the injectors are dirty.
I won't use anything but top tier gas in either my honda or toyota.
and Texaco both have techron.. That's pretty good stuff for keeping
injectors clean.. I also use shell a good bit, and it has a cleaner,
I guess proprietary vs chev/tex's techron..For the most part, all the
gas come from the same place, but it does vary as to the additives
in when they load the tankers. The cheap places don't get much extras
their gas. My honda doesn't like Valero/Diamond Shamrock too much..
I can tell the difference in the idle, etc vs chevron or shell.
So I won't even try that stuff in my toyota.. I stick to only the good
and the funny thing is, the cheap gas these days costs as much as the
good brands.. Or at least here. Used to, the cheap stations really
cheaper. But not really any more. I often see them charging as much,
and sometimes even more than a big brand sitting down the street.
So it doesn't pay to run cheap gas around here from pretty much any
BTW, my honda has a carb.. Only my yota is FI... But it still seemed
make a difference on the carbed engine if I used good gas vs cheap.
If I did happen to get a case of gunked injectors, I'd try a bottle
techron in the gas and go from there. That'll usually do the trick.
I once had to clean out a super carboned up camry one time.
The injectors were half clogged, but also the intake valves were
snowconed beyond belief.. So bad, once the car warmed up,
the carbon would expand, keep the valves from totally closing, and
engine would die from lack of compression. So I tested a few
different cleaners during that, and got a pretty comparison.
Techron really is some pretty good stuff vs some of the cheapy
regular "gas treatment" brands.. It's worth the extra money.
One bottle in a full tank will usually clean out an engine pretty
The more stop/starts with heat soaks, the better it works..
It doesn't do much when you are actually driving. It's when it's hot
and sits, that the cheese melts and then starts blasting away when
you run it the next time.
Heck, adding a bottle of techron once or twice a year, even with no
problems at all, probably ain't a half bad idea as far as preventative
upkeep if it's FI, or prone to carbon buildup.
I don't know when that came about, but I noticed it not long ago. Back in
the '60s the cheap stations were often about 10% cheaper than the 'majors' -
say, 28 cents when the majors were 31 cents. Now even ten cents is only 3%
cheaper and the top tier stations are usually not even ten cents more - as
you say, sometimes less. It's a lot less than buying equivalent injector
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