EMB Queries on a '99 NB

[elduce]

Hi all, after reading around the various fora on the net and having a look through the manual, I've got a few specific queries about running an EMB on a Miata 1999 NB 1.8 and I'm hoping you knowledgeable guys might be able answer them (I've asked the same questions on a few other fora and had not one reply so far ).

Can anyone tell me:

1) Do you need to bypass the MAF signal around the EMB on the '99?

a) if so, do you still need to put the resistor in for the MAF signal?
b) can anyone suggest an outlet to obtain the resistor holder
to hold the resitor in line (I don't really want to solder my ECU or EMB)?
c) I assume the EMB will have to run entirely off the MAP sensor if the MAF signal is bypassed?

2) Why are there two tables for adding fuel in the EMB manual (Air flow adjustment and additional injection setting)? I can understand that the Air Flow map tricks the ECU into adjusting the fueling by altering the airflow signals, but why do you need a second table to add injector duty cycle?

Does the duty cycle map take care of transient throttle situations?


3) Do I need to jumper the injector cables into the EMB as per the idiot's guide to the 1.6 NA:



Many thanks in advance for any help offered.

[Accord2nrz]

Originally Posted by elduce

Hi all, after reading around the various fora on the net and having a look through the manual, I've got a few specific queries about running an EMB on a Miata 1999 NB 1.8 and I'm hoping you knowledgeable guys might be able answer them (I've asked the same questions on a few other fora and had not one reply so far ).

Can anyone tell me:

1) Do you need to bypass the MAF signal around the EMB on the '99?

No, it must be wired into the emb as well.

a) if so, do you still need to put the resistor in for the MAF signal?
b) can anyone suggest an outlet to obtain the resistor holder
to hold the resitor in line (I don't really want to solder my ECU or EMB)?
c) I assume the EMB will have to run entirely off the MAP sensor if the MAF signal is bypassed?

A. Yes a resistor still needs to go in place.
B. I would reccomend radio shack, i believe they have inline holders or protectors for resistors.
C. No, wire your MAF sensor into the emb and put the greddy sensor on and then clamp your MAF voltage.

2) Why are there two tables for adding fuel in the EMB manual (Air flow adjustment and additional injection setting)? I can understand that the Air Flow map tricks the ECU into adjusting the fueling by altering the airflow signals, but why do you need a second table to add injector duty cycle?

The airflow map is the less effecient way becuase your car is actually going to alter ignition timing based off the airflow map. Adding via the injection table will just add fuel so you adjust timing yourself at a later date. It gives you more control to fine tune.

Does the duty cycle map take care of transient throttle situations?

No.

3) Do I need to jumper the injector cables into the EMB as per the idiot's guide to the 1.6 NA:



Many thanks in advance for any help offered.[/quote]
Yes you do.

[elduce]

Thanks Accord2nrz, that's great information. I've asked the same questions on about 4 other fora over the past two weeks and not had a single reply apart from yours.

[Accord2nrz]

Glad that I can be of some help to you. Let me know if u have more questions.

[elduce]

Just to correct the information above - on a 1999 or later Miata/MX-5, you do not connect the injector wires together in pairs, each injector signal wire is spliced to a dedicated Injector signal wire on the EMB harness as unlike the earlier cars, the 1999 and later miatas/MX-5s do not have grouped ignition.

Injector 1 goes to channel 1 on the EMB, Injector 2 to channel 2, and so on.

This is the wiring diagram you need: