So I am sitting here trying to figure out the fuel pump rewire. ( I know I should just go do it and figure as I go but it is dark.) I am using the write up at http://www.1300cc.com/howto/how2/rewire.htm

I guess what I am having trouble grasping is the connecting wires. At the connection under the airfilter your going to bridge wires E connects to F and A connects to B.

Then at the pump you connect E to A and F to B? That is what it looks like.

Also, the relay. Got a relay from advanced auto.
The package says
30H - terminal for lights or horn
86S - Terminal from switch
87B - terminal from power source
85m - terminal for relay ground wire

So I am asuming
30H - To the stock relay
86S - + from the cut pump wires (remote)
87B - 12V from the battery
85M - Ground on some bare metal

Can anybody proof that and see what they think?

This is for my 91 TII

James

 

dam it's been a while since I did it... . yes, just connect the 2 cut ends together. x2
yes and you add in the other 2 wires (fuel pump and relay) as shown in the pic. so you have 3 ends joined together. x2

looks right.

 

Wow, now that is grade A forum service That was fast man! Thanks Scott!

So did it affect gas milage? I always thought the injectors used what the engine needs and sends the rest back?

Anybody else done this mod?

 

I would like to know if this would benifit and 87 N/A

 

I've done it and it's easier than it looks. The drawing helps a lot. It didn't seem to affect the mileage at all.

A little trivia:
If you have the windows up and the radio off you can hear the relay switch when you go full throttle.

 

You bet. NA's need fuel too! IIRC, it is easier on an NA, b/c they don't have a component the TII's do. I think they are missing the resistor pack (which drops voltage at low throttle), so the rewire is SUPER easy.

 

I am not sure about this NA thing being different than a TII. I was looking in my factor wiring diagrams on section B3 and there is NO differation between turbo and non turbo. They might be the same system on a 91 RX-7.

James

 

This mod isn't about improving performance or economy. it's just to ensure the fuel pump is receiving the full voltage it's supoosed to so it can maintain fuel pressure. It the voltages drops, the pressure drops. If the pressure at the rails drop, less fuel will flow from the injectors than the ECU thinks, meaning it'll run lean. They're totally different. The NA doesn't have the dropping resistor to reduce pump voltage to 9V under light load. It just gets 12V all the time. This make the rewiring procedure as simple as installing one relay at the fuel pump. The relay is fed 12V direct form the battery and is switched by the original fuel pump wiring. Much easier...

 

Did you read my above post though...the FSM wiring diagrams made no notes on difference between a turbo or non turbo. I dunno if that is true.

James

 

well the FSM has 2 different sections for turbo and non turbo. they won't say they were diff. they just would be. did you compare sections?

 

Thanks man I have been looking for a write up on this for awhile now. Guess I know what I will be doing on my weekend off.

 

The only different thing I noticed is a one thing is connected on the na and disconnected on the turbo...i will post a picture tonight.

James