Honda Car Forum

I didn't take too many pics actually (was in a hurry).
http://www.tegger.com/hondafaq/misc/injectors/

After a bit of experience pulling injectors at the wreckers, it only took
maybe ten minutes to pull my own. But with all the checking and cleaning
and stuff, I was at it for a good hour and a half before I was done.

I first loosened the fuel filter's service bolt to relieve any pressure,
but after having sat overnight, there was no pressure left. Nothing came
out at all.

I had to move the clutch cable and tie it out of the way with zip ties, and
remove a couple of vacuum lines, but once I did that, the three fuel rail
nuts were all it took to unbolt the fuel rail and push it back. A careful
wiggle and lift had the rail off the injector tops. A little fuel dribbled
out, just enough to wet the top of the intake manifold runners a bit. It
eveporated in less than a minute. There was no need to undo the pressure
regulator or anything else except the two vacuum lines.

Those three fuel rail hold-down nuts are difficult to keep hold of. I
dropped two of them twice. Lost one, but luckily I had an identical
replacement in my jumble in the basement (whew).

I pulled injectors from several cars at the wrecking yard, just to get an
idea of what they were like at various mileages (I put them back after).
Well guess what? No matter whether they had 267,000 miles or 95,000 or
something in between, they all looked IDENTICAL, even in the one car that
had a seriously oily PCV system. So what's all this about "dirty
injectors"?

The very tip of ALL the injectors were universally clean as a whistle both
inside the pintle recess, and all the way out and up the pintle shroud
maybe 1/8" up. Above that, ALL of them were badly crusted with gummy black
carbon that ranged from 1/32" to 1/16" in thickness depending on exact
location. My #3 injector's carbon appeared "wetter" than the rest. I wonder
if that one was leaky.

The carbon smells vaguely oily/gasoliney.

I found it passing strange that not a single injector I pulled had anything
at all in the way of deposits anywhere inside the pintle recess. Not a
single speck. No gum, no carbon, nothing. Zero. Zilch. Squeaky clean. Each
pintle moved inwards slightly with equal resistance when pressed with a
skinny plastic stick.

All the filter baskets were likewise perfectly clean, with no sign of gum
or dirt. Each one admitted identical light when held up to the sky.

The downstream side of the injectors (towards the valve) was the dirtiest,
probably due to eddying of the airflow on that side.

One thing I noticed was that the filter basket had a tendency to pull out
of the injector top and stay in the fuel rail. A pair of eyebrow tweezers
carefully applied was enough to extract it when that happened.

I carefully wiped off the tips of each injector with throttle body cleaner
and a rag, made certain there was no dirt in the pintle recess, sprayed
throttle body cleaner to remove any that might have migrated there,
replaced all the rubber sealing rings (three of them per injector), and
moved my original filter baskets to the new injectors.

After lubricating each new upper O-ring, I was careful not to pinch them
while reinserting the injectors back into the fuel rail one by one. Then
each injector had to be fed through each manifold runner hole after they
were all in place in the rail. I found it worked best to feed in #4, then
#3, then #2 and so on, angling the rail as I went.

It was an educational exercise, but ultimately probably a useless one, as
it had no effect on engine performance. I'd say that Keihin injectors are
impressively reliable. My guy, for one, says in twenty years he's never
seen a Keihin injector go bad. Probably why they cost $287 each.


--
TeGGeR®

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

Nice.