Fuel injector o-rings

[The Critic]

I think this is how cars can mysteriously catch on fire and burn to the ground after engine repairs.

I was replacing the Valve Cover Gaskets on a 2006 ES330 with 46K miles. In order to improve access to the valve covers, the fuel injector harness gets disconnected. Due to the stubbornness of these connectors (after being in place for 19 years), you have to give the connector a good wiggle in order to disconnect it. As a result, the injectors also got wiggled.

During this process, I noticed some dampness at the top of the injector (near the rail) and smelled some fuel. For safety I decided to replace the upper and lower o-rings, and also the cushion. While doing so, I found a few of the injectors to have torn lower o-rings and one of the upper o-rings was swollen.

I don’t know if this would have resulted in an active fuel leak, but I think any fuel seepage should be taken seriously and replacing the injector o-rings was worth the investment.

 

[bdcardinal]

They are generally inexpensive so the only reason to not do it is from being lazy or not caring. The Ford service manuals usually all say to replace the o-rings when removing an injector, especially on the direct injection ones.

 

[vavavroom]

O-rings are one-time-use items. And their lifespan is not indefinite even if they remain undisturbed. Whether or not it matters or is a safety concern depends on the application. Skin contact with benzene is awesome.

 

[slacktide_bitog]

The last time I had to replace an injector, it didn't come with the O-rings, had to buy them separately

I don't understand why new fuel injectors don't always come with new O-rings.

 

[KrisZ]

If they weren't disturbed, they would've likely been fine. But this shows just how little it took to compromise the seal with such old o-rings. Something to keep in mind I guess because it may delay your job significantly if you cannot source these o-ring fast enough.

 

[MolaKule]

Mmemeber @Trav does a lot of injector work.

You might PM him re. this matter.

 

[ElectroMechanoMan]

I replace o rings on anything I take apart unless I don’t have a correct replacement and I’m under the gun to get a piece of machinery running. I definitely check for leaks in any case.