Fuel Injector Harness Question

[big911fan]

I want to check the resistance across my fuel injector terminals and need to remove the injector harness.

I know it has clips on the harness but don't know if I can just pull the harness off the injector or do I need to lift the clip somehow to remove the harness from the injector.

[old school 911]

I just removed my injectors to be serviced.

1989 3.2

I was able to remove the injector terminals just by pulling on them with a slight "wiggle".

[big911fan]

How big of a PITA was removing the FI rails to get at the injectors. Ultimately I'd like to send mine out for a rebuild also.

On the left bank (cyl 1-3) there is a bracket holding the three sensors and on the right I have the a/c compressor which I know I can roll over after loosening everything. I did it for the plug replacement on cyl 4-6.

Anything else that's going to cause a real PITA. I'm getting too old for blood sports...

Also, where did you send the injectors for rebuild? I've heard Marren FI in Conn. is good and RC FI in Torrance, CA is good. Since I'm in CA it may be quicker a time to RC if there are good reviews about them.

[mepstein]

Mr Injector. $17.50 each. They come back with flow sheets before and after. Look and work like new. Couple day turn around. I've sent him over 100 injectors and pleased every time.

[Pedro '84 Coupe]

Remove the heater duct and heater blower motor and you should have plenty of access to the driver's side. I was able to get at the driver's side without removing the A/C compressor, but I did remove the AFM, boot and air filter assembly. Use a pick tool or small screwdriver to loosen the clip on the connection to the injector. Also make sure you have a magnetic pickup tool in case the u-shaped retaining clip flies off somewhere. Have some rags or shop towels ready for any gas spillage. You may want to relieve the fuel pressure before digging in.
I took a few pictures when I removed my intake manifolds that show the fuel rails. If you want, PM me your email address and I can send them to you.

[old school 911]

Originally Posted by big911fan

How big of a PITA was removing the FI rails to get at the injectors. Ultimately I'd like to send mine out for a rebuild also.

On the left bank (cyl 1-3) there is a bracket holding the three sensors and on the right I have the a/c compressor which I know I can roll over after loosening everything. I did it for the plug replacement on cyl 4-6.

Anything else that's going to cause a real PITA. I'm getting too old for blood sports...

Also, where did you send the injectors for rebuild? I've heard Marren FI in Conn. is good and RC FI in Torrance, CA is good. Since I'm in CA it may be quicker a time to RC if there are good reviews about them.

Honestly, it is not too bad. As mentioned, remove a few items on the dr side (I removed my blower motor as well). I was not in a rush and for the most part only a few brackets to remove to clear the path. For the pass side I removed the air box and unbolted my ac compressor.

Before removing the injectors, I cleaned the surrounding area and juiced the lower o-rings with wd 40.

I live in Torrance, so RC Fuel Injectors is ~4 miles away. I checked the impedance and then drove them over around 3:30 PM. Received a call the next day around noon, picked up and fired up in a few hrs. Cost was $25 per.

Here are a few pics and my flow results.

[old school 911]

[big911fan]

Thanks for all the tips. Now I need to decide how lazy I am.

Looks like FI cleaning is very effective based on the before/after results.

Have you noticed a big difference in driveability, performance, mileage, etc?

[old school 911]

Originally Posted by big911fan

Thanks for all the tips. Now I need to decide how lazy I am.

Looks like FI cleaning is very effective based on the before/after results.

Have you noticed a big difference in driveability, performance, mileage, etc?

Noticed a smoother idle...do not drive enough to notice mileage as far as performance it feels like response is improved.

[spuggy]

Originally Posted by big911fan

I know it has clips on the harness but don't know if I can just pull the harness off the injector or do I need to lift the clip somehow to remove the harness from the injector.

It's an AMP Junior Timer connector. If your plug has a metal bar, squeeze it towards the body and that releases the clip(s) and lets you separate them.

You shouldn't be able to pull the two connectors apart without depressing the spring clip if both sides are in good condition. It is supposed to hold them locked together.

They get old, and some spring bars require almost no pressure - or the locks get damaged and don't hold the connectors together as securely than they should.

[mepstein]

All the ones I’ve sent have gone from way out of spec to near 100% correct. It has to be better for an engine to have an even amount of fuel injected in each cylinder. It also comes back with new seals. They don’t last forever.

[old school 911]

the connectors i had to remove did not have any space to push.

[RedCoupe]

Originally Posted by old school 911

the connectors i had to remove did not have any space to push.

I think the clips are supposed to go on the other way so you press in the area that has that open space. It's the ends of the clips that hold the connectors together, so pressing the clip deforms it and spreads the ends of the clips.

[spuggy]

Heh, OK, I have literally no clue how that's supposed to work... Maybe the spring bar just offers a little resistance and you do just pull 'em off...


I had this type on my AAR/WUR connectors:



Just trying to pull those off won't go well/isn't how its done...

[timmy2]

Originally Posted by RedCoupe

I think the clips are supposed to go on the other way so you press in the area that has that open space. It's the ends of the clips that hold the connectors together, so pressing the clip deforms it and spreads the ends of the clips.

Those connectors are sent that way from the factory. Nothing wrong with them.

Wiggle and pull to remove.

[old school 911]

Originally Posted by timmy2

Those connectors are sent that way from the factory. Nothing wrong with them.

Wiggle and pull to remove.

yes, that is what I did to remove..slight side to side and pull.