Nissan: Bosch type Fuel Injector Connector Repair and Replacement
By Vernon Husk aka "Son_of_Z" on Zcar.com
Recently I was faced with the daunting task of replacing two of the Fuel Injectors (FIs) on my 1977 Datsun 280Z. Naturally, in removing the two prong electrical connectors from the FIs the connectors broke and required replacement. These cars have been on the road for almost 30 years now and these small plastic peaces have deteriorated from heat, oil, fuel and other contaminants in this hostile environment. Therefore, I decided to go ahead and install all new fuel injector connectors at this time as I was waiting on a new Heater Control Valve anyway for the next 2 weeks and my Z was down for those parts.
There are a total of 10 of these connecters required to do the complete engine:
6 for the fuel injectors
Thermo time switch
Cold Start Valve
Water Temperature Sensor
Aux Air Regulator (AAR) Valve.
Anyone who has ever removed one of these stock Nissan connectors knows what a pain in the rump they can be. I use a Dental Cleaning Tool and two small flat tipped screwdrivers. It’s kind of like an elephant doing open heart surgery on a Hummingbird with a pick axe and shovel if you get my drift. Even though the need might be seldom and a long time in-between to disconnect these connecters in the future, I was determined to find a better mouse trap AKK Fuel Injector Connector.
Old corroded terminals on bottom new on top Which do you think work better?
I tried a variety of 6 different types of connectors supplied by several suppliers (whom I won't mention because I still do business with them) and they were all a variation on the stock Nissan part and all but 2 required the new connector to be spliced into the wiring harness and soldering the new connector pigtail into the wiring harness. When you do this, no matter how good you are with a solder gun it seams to always look like a snake that has swallowed a big rat and the rat is mid way in your wiring harness. I preferred the type that has new female terminals that you crimp on the wire just like it came from the factory. Now there are some people that will say crimping verses soldering, soldering wins but if done correctly with the proper tool the crimped terminals should last another 30 years and look a heck of a lot better. The final piece that is necessary for a good IF connector is a rubber boot to protect the connecter 4 of the 6 connecters I tried did not include a rubber boot. So the 3 primary things that are required (in my opinion) in a new replacement connector are ease attachment / detachment, crimped terminal connections and new rubber boots.
I asked the Parts guy at my local NAPA store if he could get me the BOSCH type connecters that were originally designed to be used with this fuel injection system on German cars to see if they met my requirements for replacement. NAPA did not carry the part however he had a BOSCH catalogue and looked up the part and ordered it for me, he said that he got the connector from a BOSCH supply warehouse.
BOSCH part number is 1-287-013-003-000 and the label said Made in Germany. Cost was $12.00 each with tax.
Convenient and integrated "Press to release" mechanism that out performs the original connector's troublesome wire clips that frequently fly off or cause cracking.
This is a connector repair kit that contains; 1 rubber boot, 1 plastic connecter with spring clip, and 2 female spade terminals. What is cool about this connector is that the spring clip can be depressed with your index finger to release the lock wire while you disconnect the connector. This is a pain free, no tools required, 1 handed operation that wont be a dreaded job to do whenever you need to get access to the injectors and that feature alone makes these connectors worth every dime they cost.
Here is a picture of the new connector boot and pin on the left with an old connector and corroded pin on the left.
NOTE (pin polarity on fuel injector connectors):
The pin on the "front of car side" of FI connector is +12V and the pin on firewall side of car gets grounded by ECU to fire the injector
+12V on injectors 5 & 6
Passenger side view of all 6 showing +12V side (facing front of engine)
Disconnect Negative Battery Cable
Make sure you have the necessary tools and the appropriate numbers of connector repair kits too do the job.
2 small flat tipped screwdrivers
Terminal crimpier (you should be able to pick up a [pair of these at Radio Shack)
Dental Cleaning Tool (ask your Dentist they always have a handful of old ones to get rid of)
Some Heat Shrink I use 10 – 18 gage
The new connector and boot are in the lower left with shrink tube
Disconnect 1 terminal at a time by using the dental tool to push the steel spring clip under the locking tip on the plastic connector.
Then get underneath the spring clip with 1 or 2 of the screwdrivers and gently slide the spring clip up and off the connector.
Then the connector can be removed from the injector.
This is the time to clean the MALE terminals before installing the new connectors I use an emery board for this they work excellent.
These connectors have 2 wires
that run through them and they can NOT be interchanged, they have to be
reconnected to the correct terminal.
The top of the connector is
flush with the two sides while the bottom has a finger sized grove that is
necessitated by the clearance in relationship to the injector when
installed. We will be working looking at the bottom of the connector
on all of them so as to not get the wires crossed or confused.
trim back the plastic protective tubing that covers both wires about 2
inches, being careful not to damage the insulation on the individual wires
Working on the Thermo time / water temp sensor harness on the table but the fuel connectors work the same way.
Now holding the connector so that the bottom (grooved side) is up and the connector opening is facing away from you cut the wire on the RIGHT about 1/16 inch from the old terminal.
Strip ¼ inch if the insulation from the wire you just cut and install a female terminal. This can take a little practice just make sure you have the proper crimping tool or it will never be right. Each terminal requires two crimps 1 for the striped portion of the wire and the other for the wire with the insulation still on. This last crimp is important as it is what holds the wire to the connector while the first is important because it makes the actual electrical connection.
- Next cut the wire on the LEFT side about 1/16 inches from the old terminal.
This shows the shrink tubing in place and shrunk, the rubber boot inverted half way and installed, and the new terminal crimped on the Right side wire ready to slide into the connector except the Locking TANG is turned down so just role it over then insert.
Slide a piece of shrink tubing 2 inches long over the two wires and about 1 inch up and over the old plastic protective tubing that you trimmed back earlier. Shrink the tubing down on the wires and plastic insulation as to have a very snug fit. You can use a heat gun to do this I like to use a BBQ lighter.
Take a rubber boot and roll the large end inside out, later this will allow you to easily slip the boot over the new connector. Slide the rubber boot, small end first up and half way over the shrink tubing that you just installed.
Here is the old rubber boot on left new on right.
Now you install the RIGHT side terminal into the new connector while holding the new connector in the same position as you did the old one when cutting the wires. Attention the female terminals are locked into the connector with a tang that protrudes out the top of the connector make sure when you insert the terminals into the connector this tang is orientated correctly, which is tang to the bottom side of the connector. Failure to do this last step correctly will allow the terminals to float freely in and out of the connector resulting in a bad connection.
you strip and install a female terminal on the LEFT wire in the same manner
as you did the right and install it into the connector.
Slide the rubber boot a little towards the connector and roll the large end over the new terminal for a snug fit. Congratulations you have just finished your first connector replacement the subsequent ones will get exponentially easer.
Both terminals inserted and rubber boot ready to be unrolled into place