4.0 Fuel injector

[Carl Saiyed]

BTW, I passed on the 266k YJ.

Drove the Jeep (89 Cherokee 4.0) all day yesterday and today without issue.
Started it up about 530pm today to go pick up a date and smelled fuel...
bad. I've noticed my gas mileage has been a little down lately, but I was
getting about 10mpg today. Power is down, the idle is rough.

Stopped at a gas station, and while fueling up I checked under the hood. I
can see fuel leaking from the top of the injector where the green plug
attaches to the injector.

Do I need a whole new injector or just an O-ring? Do I need to replace all 6
injectors? At 70 bux a pop, I'd like to replace one at a time if possible.

Advice on changing an injector? Brands to stay away from?

Thanks,

Carl

[Will Honea]

Within a week of getting my 88 MJ ihad 2 of those suckers pull that on
me. Did you happen to notice hwere that fuel runs as it leaks out?
Yep, right down on the exhaust. If you have fuel around the
electrical connector, they are toast - replace them. Of course, you
should also replace ALL the o-rings (12) when you replace the injector
- and don't forget the ones for the feed line and the pressure
regulator. You have to pull the fuel rail anyway, so it's cheap
insurance.

I bought the aftermarket injectors from Advanced Auto - not cheap but
a whole lot cheaper than the dealer. The ones I got use a different
plunger in the nozzle and I actually like it better than the OEM -
lower mass and forced closure. They have been in for nearly 50k miles
now and no problem with them at all.

--
Will Honea

[Carl Saiyed]

Tx for the advice. How do I pull the fuel rail?

Carl

"Will Honea" <who...@yahoo.com> wrote in message
news:JxX2tWiP5BNp-p...@anon.none.net...

[Kevin in San Diego]

There are bolts that hold it down and clips on the injectors. Also there are
o rings on the fuel rail that can get lost. Be careful with those as well.
You need a manual it sounds like. there is also fuel pressure to bleed off
before you yank it apart.
KH

[Will Honea]

Kevin makes a good point - a manual will save you serval times it
price over the life of a Jeep.

You don't necessarily have to pull the fuel line on the 88/89 but it
has a pressure regualtor sittin at the front end of the rail attached
to the return line. You can loosen the clamps that hold the return
line in place to get enough room to work, but it's easier just to pull
the regulator off the rail before you start - take the O-ring that
seals it to the rail with you and get a new one at the store while
you're there - make sure it's rated for fuel line use. If you DO pull
the fuel line, also pick up a package of the plastic clips to use when
you re-install it.

There are 3-4 small bolts that hold the fuel rail on the manifold.
They may be stuck and take a pretty good pop to start out of the
aluminum threads, but don't carried away when you put them back - good
and snug but hauling away on the wrench will strip threads. Short
screws into aluminum are touchy.

A shop manual will save you losts of grief.

On Mon, 21 Mar 2005 13:16:06 UTC "Carl Saiyed"
<carls...@REMOVEhotmail.com> wrote:

--
Will Honea

[JohnM]

Will Honea wrote:

>
> There are 3-4 small bolts that hold the fuel rail on the manifold.
> They may be stuck and take a pretty good pop to start out of the
> aluminum threads, but don't carried away when you put them back - good
> and snug but hauling away on the wrench will strip threads. Short
> screws into aluminum are touchy.
>

To ammend the above, use NeverSeize on fasteners going into aluminum
(unless specifically forbidden). Buy the big bottle. Use it on everything.

For exhaust manifold bolts and studs, use pipe dope. The gritty or
chunky looking stuff is *much* better than the smooth and creamy. Pipe
dope doesn't cook out like NeverSeize (even the alleged high-temp
variety ain't so great).

John

[DougW]

Carl Saiyed did pass the time by typing:

> Tx for the advice. How do I pull the fuel rail?

1) release pressure at the test port
2) remove the screws holding it in
3) slowly work the injectors out of the manifold
(grab and twist, it takes some effort)
work one at a time to minimize stress on the rail and
don't use the rail as a handle, it's more expensive than
the injectors. :/

4) get a glass jar ready, the rail holds lots of fuel and
there isn't any sense in wasting it. (not at todays bloody
high prices)

5) pull back the fuel return line and supply line
(some use clips, some use a spring lock, YMMV)
and remove the lines.

6) take the rail over to that glass jar you have

7) Remove the clip from the back injector and with the
fuel rail ports stuck in that glass jar you have.. :)
slowly wiggle the injector free.

8) take the rest of the injectors off. There will be quite
a bit of gas left in the rail and injectors.

hint: it's better to work on the clips while sitting on the
garage floor. things that fall a short distance tend not
to bounce very far. :)

I use a toothbrush and some TB cleaner to clean the rail
ports and manifold ports. To put the injectors back you
just do the reverse, a bit of oil on the o-rings will make
it easier to slide them in. Try to keep even pressure on
the rail (work one injector a bit at a time)

The rail bolts don't hold back any pressure. Use a nut
driver and when they seat give a bit more.

--
DougW

[Carl Saiyed]

Thanks all. I was able to replace just the 12 O-rings. The injectors didn't
look fantastic but didn't look bad. I was able to wrestle the clips off
without removing the rail from the return line. Is anything wrong with
GP-Sorenson injectors? Autozone has them for $45, while CSK has Niehoff for
$76. Are all injectors made equal?

Carl

"DougW" <post.r...@invalid.address> wrote in message
news:NJJ%d.15$WM6.13@okepread07...

[L.W. Hughes III]

Hi Doug,
You should add this documentation to your helpful pages at:
http://revbeergoggles.com I was going to put up what the Factory Service
Manual says, but takes into consideration we already know how to change
an O-ring: http://www.billhughes.com/XJfuelinjection.pdf
God Bless America, ßill O|||||||O
mailto:LWHug...@aol.com

[DougW]

L.W. ("ßill") Hughes III did pass the time by typing:

> Hi Doug,
> You should add this documentation to your helpful pages at:
> http://revbeergoggles.com I was going to put up what the Factory Service
> Manual says, but takes into consideration we already know how to change
> an O-ring: http://www.billhughes.com/XJfuelinjection.pdf

I'll do that.

But now it's time to log off. My UPS went POOF and there is a
thunder storm in the area.

--
DougW

[Kevin in San Diego]

Toto?
KH

"DougW" <post.r...@invalid.address> wrote in message

news:mFK%d.34$WM6.31@okepread07...

[Jerry Bransford]

Ooohhhh... The Doors... what a band, love that song.

twaldron wrote:
> No. The Doors...Rider on the Storm.
>
> Kevin in San Diego wrote:
>
> Toto?
> KH
>
>
>
--
Jerry Bransford
PP-ASEL N6TAY
See the Geezer Jeep at
http://members.cox.net/jerrypb/


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[twaldron]

No. The Doors...Rider on the Storm.

Kevin in San Diego wrote:
> Toto?
> KH

--
___________________________________________________________
tw

71 Bill Stroppe Baja Bronco
03 TJ Rubicon - Rubicon Express 4.5"
01 XJ Sport

There is a very fine line between "hobby" and "mental illness."
-- Dave Barry

Pronunciation: 'jEp
Function: noun
Date: 1940

Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
A small general-purpose motor vehicle with 80-inch wheelbase,
1/4-ton capacity, and four-wheel drive used by the U.S. army in
World War II.

(Please remove the OBVIOUS to reply by email)
___________________________________________________________

[DougW]

Kevin in San Diego did pass the time by typing:
> Toto?

I hope not.

The UPS failed yesterday and that means I have to
plug the PC into ye olde power strip.

> "DougW" wrote ...