A follow-up to my previous post... but different enough I felt a new thread would be in order.

I recently purchased some 94 EX injectors on eBay:





Upon removing my current injectors I found the ends were different:





(Crummy pics, I know) It appears that my injectors had a secondary plastic cap that slid over the original plastic end as seen in the first two pictures. I was able to get the secondary cap to wiggle and slide off 1/16th of an inch or so, but it seemed like it wanted to break before coming off.

I ended up replacing the two bad (leaking) injectors with the non-capped eBay injectors and leaving the other two capped injectors in. The car runs completely normally except for an ever-so-slight bit of roughness in the first millisecond of startup.

Anyone know the story on these secondary ends? Are they removable or replaceable? Are the necessary? They look at though they were intended to modify the flow pattern of the spray. But then why is there a little o-ring at the end?

 

Obviously, o-ring's job is for proper seal. Very good tip: Injectors are flow matched to each other in a pack so DON'T mix it, no half new and half old! Hope you bought peak n hold type.

 

Well the four "new" ones were used injectors, so I don't think flow matching is an issue.

They must be peak-and-hold type since the 2 "new" injectors worked. That is, the car starts up and runs with no apparent changes.

There is another larger o-ring that seals the body of the injector against the intake manifold. I can't image what the other o-ring is sealing against!

 

I had that on my precision injectors, doesnt matter dude just slap them in,it wont fall out, if you don't have any vacuum leak ur fine. BTW, even if they are used, they must of had it cleaned and flow matched. They should of supplied you with the results sheet otherwise, you've bought it from dodgy egay seller.

 

What exactly did you have on your precision injectors?

I believe they were injectors simply pulled from a working vehicle that had been parted out.

 

The new injectors that you bought look like they are from a 96-97 F22B1-B2 that doesn't have the Fuel Injector Air control system (FIA). That is why your old injectors look the way they do. They are meant for the FIA System and have a double seal to keep the air going straight through the nozzel.

 

GhostAccord - thank you for that information. That is really frustrating because the eBay seller specifically listed it as a 94 EX set of injectors.

Can you explain what the FIA system does?

Thanks!

 

It was one of Honda's attempts at making a better fuel burning/economy system. They only had it on the 94-95 F22B1 IIRC. So that goes to show how useless the system was.

It is a system that allows air to flow threw the base of the intake manifold and into the injectors at certain RPM & load conditions. If you look inside the injector port you should be able to see a small opening at the top.

Most people (myself included - remove the solenoid and cover the vacuum nipple above the injector on the base or the IM. The injectors you have will work just fine if you remove the FIA system. It will not cause a CEL to be thrown.

I can post pics after I get home if you need more information.

 

Ghost Accord,

Yes, please post up some pics. I am definitely interested in removing the FIA system in order to simplify things.

So in your opinion, the FIA system is irrelevant to engine performance or economy?

 

I have never done a study on how well worked. I only know that Honda only used it on the F22B1 engine for a short time. So I would assume it didn't gain as much as they thought it would.

Here is the best pic I could come up with. I don't have any pics of the actual solenoid. It is a black cylinder, with an electrical connection and two vacuum hoses, sitting on top of the EGR manifold in the middle of your lower intake plenum.

Here is a vacuum diagram for the system.



Cap the two red vacuum ports and remove/disconnect the blue solenoid.

Hope this helps.

 

Thanks GhostAccord. I have a FSM and recognized the device right away. I'll try capping the two ports and see how it goes. So the computer won't care if the solenoid is unplugged?

 

I've never seen a code for it.