: Fuel Rail / Fuel Injector Removal

06-04-09, 03:10 AM
Am I correct in my understanding that the Fuel Injectors are connected to the Fuel Rail and that the Fuel Injectors are indirectly held in place by the bolts that hold the fuel rail in place? Otherwise the Fuel Injectors just sorta ... sit there.

The act of disconnecting the electrical connections and removing the fuel rail (and all the other junk in the way) will take the fuel injectors with?

I've not worked on a Fuel Injected system before and I've got a serious case of "I'm guna **** it up" syndrome.

06-04-09, 10:20 AM
You are correct in your understanding. Easier than it looks or sounds. Use a little engine oil on the injector O rings when you reinstall them.

06-04-09, 11:04 AM
Any advice on what the easiest way to drain the coolant is? I'm pretty sure I need to get that pipe that coolant pipe out of the way before I can lift that Fuel Rail.

Do I actually need to tear out the splash guard to get at the radiator drain valve or is there a simpler method to disconnecting the coolant pipes/tubes without getting coolant all over the place?

06-04-09, 11:14 AM
It is easier to remove the splash shield to get to the drain and less messy, but it can be done without it. Probably will have to make a "special tool". A 3/4" dowel rod with a slot cut across the end to open the drain plug that is recessed behind the splash shield. Easiest (and messiest) is to just pull the lower radiator hos, but as you can see it is not at the bottom of the radiator so it will not drain as much.

06-04-09, 10:47 PM
So here I am with everything out of the way and unbolted, all I have to do is pull the fuel rail up and take the injectors with ...

From everything I have read, it should just be a matter of pulling up on the fuel rail.

I can't seem to get it to move. To be clear, the fuel rail wiggles or bounces slightly when I nudge upwards on it. The Fuel injectors just wont come out of their sockets.

When I pull upwards, it LOOKS like there is more play above the fuel injectors then there is below them ... almost as if I could just yank the rail off of the injectors if I kept pulling.

Am I being a panzy about this or is something wrong?

06-04-09, 11:10 PM
Each injector has an O ring on it to fit firmly and seal in the hole. I think you just need to lift a little harder if all the hold downs are loose (I think there are 4).

06-04-09, 11:47 PM
In addition to what Ranger mentioned, little trick: Give each injector a good shot of silicone spray at the base, wiggle the fuel rail slightly to work the silicone in the injector holes, go and grab a snack or beer for a bit, and when you return the fuel rail with all the injectors will come out as smooth as silk (and go back in the same way). Works every time.


06-05-09, 12:52 AM
Oh, that's a good sounding tip and a good excuse to grab a beer.

I decided to wrap everything up for the night. I was losing daylight right quick and a wind storm is brewing. Less than 30 minutes after I re-cleaned random debris out from under the hood, what can only be described as the entire contents of a flowering bush was deposited on top of the Intake Manifold an intense gust of wind. That would have been (begin sarcasm) really awesome if I had actually gotten the fuel rail and intake manifold removed ...

06-05-09, 09:53 AM
:tisk: DO NOT use any silicone spray. I remember the Guru saying that silicone is instant death to an O2 sensor. Silicone on the injector is a direct path to the combustion chamber and then exhaust system.

06-05-09, 06:01 PM
Well it's a good thing that I don't own any silicone spray then.

I was planning on substituting a couple drops of motor oil but otherwise following jjm01's suggestion to try to loosen the fuel injectors up a bit.

Of the 8 injectors, I was able to get one of them (one of the rear injectors) to pop out somewhat easily, so I got a pretty decent idea as to how much pressure should be required to pull them out. The other three rear injectors feel like they are also ready to pop out with a bit more force.

It's the four front injectors that are being a real stubborn pain in the ars.

I'm figuring that neither of the two previous owners have ever bothered to have the fuel injectors serviced, which would likely mean that they have never been removed ...

06-05-09, 06:06 PM
I've never removed the injectors on any of my cars or "had them serviced". How and why do you service an injector?

06-05-09, 06:28 PM
I assume 'servicing them' is either having them cleaned or replaced if they have gone bad ...

Maybe I'm reading too deeply into a couple threads I have seen on these forums, but I thought it was a good idea to at least have your injectors cleaned once every 50k to 100k miles or something.

Then again, this is all just a poorly educated guess on my part.

06-05-09, 06:40 PM
Injectors are pretty reliable and fall under the if it ain't broke, don't fix it category. My wife's '96 Bonneville has only had the injectors pulled once to replace the intake manifold. Even then, they where only pulled and reinstalled. 160K to date and they are untouched other than the afore mentioned removal. My '92 Deville had 125K when I traded it and they likewise where untouched.

06-05-09, 07:40 PM
As a sort of aside to the injector cleaning thing, how often do/did you tear down a carburetor to clean the jets ?

I'll go back to my old saw......Google "top tier gasoline" and "chevron techron". (with GM's recommendation........)

06-05-09, 09:00 PM
Use WD-40 then, though silicone is probably better on the injector and seals.

Granted no chemicals of ANY kind should used be used near O2 sensors, but I highly doubt that tiny bit of silcone that might leak past will cause any issues. It's mostly gonna burn up upon ignition. Never had an issue with O2 sensors, and I've been doing this for years. And I put miles on my vehicles.

Even if the silicone did damage the O2 sensors, that's probably preferable than pulling hard on the injectors and fuel rail, possibly distorting the injector spray pattern, leading to a very difficult to diagnose problem down the road.

If we're gonna fret over O2 sensors, we shouldn't clean out the intake ports either for that matter... with all those nasty solvents.


06-05-09, 09:11 PM
You may well have a point. I don't know. Just passing along what I was told by GM powertrain engineer for what it's worth.

06-06-09, 04:52 AM
I would like to report back that this trick worked like a champ.

I used a Q-Tip to place a little bit of motor oil onto the Fuel Injectors. It didnt take much.

I pulled up on the fuel injectors a bit to try to get the O-Rings a little more exposed and then I soaked up some motor oil with a Q-Tip and pinched it between the backside of the fuel injector and the part of the Intake Manifold that holds the Fuel Injector in place. I then wiggled the fuel injectors a bit and waited.

I came back a few hours later and pulled up a bit and they all just popped out with a good yank. Now I can move on to pulling out the Intake Manifold and finally replace my plenum.

Although I managed to snap the small plastic pipe that runs between the Throttle Body and the Fuel Pressure Regulator in the process ... :alchi:

06-06-09, 07:34 AM
So ... about this formed rigid plastic tube that runs between the throttle body and the fuel pressure regulator (at least I am pretty sure its the fuel pressure regulator) that I managed to snap.

What are the odds that in the very short term I can get away with substituting a piece generic vacuum hose until I can get a "proper" replacement part from a dealer?

I'm assuming that piece is a dealer only part ...

Lesson Learned: Make sure you actually have everything disconnected ... and have enough light to see everything ... and yank gently

06-06-09, 09:24 AM
I think that is just vacuum supply to the FPR. A vacuum hose will work just fine.

06-06-09, 01:12 PM
Ranger is correct........You can replace ALL the plastic vacuum piping with parts-store blister pak vacuum hose of the correct size for one heck of a lot less $$$ than dealer parts. Not quite as cutesy, but more functional.