10srotary

i have installed a 13bt motor in my 1988 mazda rx7 gxl. the motor is in but i have ran across some porblems finding the ecu? and there are two plugs tht do not match up on the drivers side. i would just like to know what i need to do to complete the wiring. thanks alot, any information would help!

RotaryEvolution

iTrader: (30)

the ECU is under the passenger side carpet

how did you swap the motor without knowing where the ECU was?

10srotary

you dont have to take out the ecu to get the motor out.

Gringo Grande

iTrader: (97)

I believe he is questioning how could you have the knowledge to swap the motor but not have any inkling where the ECU is. Unless you just hoisted one motor out, another in, and have no idea what you are doing from there. =D

GG

10srotary

i have never delt with a rotary engine before. they have to be the most complicated engines in the world. i have already finshed most of the wiring on the drivers side, there are just 2 plugs tht do not conect where they have to go, i read on another forum tht you have to change to plugs, i am just wondering if thts the 2 you change. usually the ecu is under the hood beside the engine.

10srotary

thanks for the info on the ecu, grately appreciated!

Aaron Cake

iTrader: (1)

The Factory Service Manual can be found in the FAQ For FC thread. It contains all this information and more, and is an essential tool for any sort of service work that needs to be performed on these cars.

Additionally, the Haynes service manual for the 1986 thru 1991 RX-7 (both turbo and NA) can be found at most local auto parts stores or purchased from any good bookstore (ISBN number 1 56392 007 7). It is only about $25 and is a great quick reference for things like this. Not only does it contain most of the information in the FSM condensed into an easy to read format, but it includes full wiring diagrams as well.

These manuals will answer 99% of service related questions for the car and if you intend to do your own repair work, you will need at least one of them. Preferably both, since the FSM is a free download.

HAILERS

The other LARGE plugs on the USA harness connect to the Front harness connectors that are above the passengers legs and far right.

IF you used a series five harness and ECU on a series four.......forget it.

arghx

iTrader: (3)

to get to the ECU, pull off the passenger side scuff plate thingie, then the passenger side plastic corner kick panel thing (there are 3 clips on it, you can't miss it. Then pull back the carpet and you will see a big metal plate. Remove the nuts to take the plate off and it's right there.

10srotary

i have swaped engines on a few older ford models before but never had much problems with the electrics how do i tell if my car has a series 4 harness or my new engine has a series 5 my car is an 88 and i bought the engine as an 88 too

10srotary

i have replaced a few engines before (all ford)but never changed to a different model i bought an 88 13bt to replace my 88 13b and was led to believe i was getting a full harness with it and it would be a drop in not so the jdm 13bt needs to be conected to the existing harness and its getting confusing

HAILERS

The harness that connects to the engine and runs along the right side of the engine bay is the EM harness. It connects to the ECU under the passengers feet inside the car (and a few more places in the car). If it were a series five harness it WILL NOT IN ANY WAY connect to the series four ECU. AINT' no way.

So if it does connect, then alls well.....on the whole. Right series anyway. It'll even plug into a series four non turbo or turbo ECU.

HAILERS

We need an answer that may solve your problem. Is this EM harness a JDM harness???????????? or a USA one.

One way to identify a JDM harness, is that it won't have the connector for the wiper motor. That's a sure clue.

Say it is a JDM harness. Personally I'd put it in the attic and use the original harness that was in the car. After all, all RX have four injector, a afm, boost/pressure sensor , tps, etc, etc, etc,

The car should start and run with the original harnes. Just a couple of minor changes to the n/a harness (maybe two wires, I'm starting to forget exactly).

cpubugs

Yeah 3 moving parts Vs. over 140 moving parts ...


very complicated...




I don't think the engine is what you are refering to as complicated.

cpubugs

All of my honda's ECU is in the cab, My Nissan P/u truck, in the cab, my rx7 in the cab. The ECU is usually in the cab, it is dry and usually not so warm there. I can't think of any car I have ever owned that the ecu is under the hood anywhere near the motor. But thats just my experience.

Aaron Cake

iTrader: (1)

For some reason, American cars seem to have the ECU under the hood. Unlike the Japanese, American manufacturers thought it was a good idea to put sensitive electronics into an area directly effected by heat, dirt, moisture and corrosion. What's even worse is that some of the aftermarket EFI kits of these engines put the ECUs on TOP OF THE ENGINE between the cylinder heads...

ItsTimesLyke

sry to intrude, but this seems like a good place to ask this ?, i have a 87 s4 glx and have found an S5 TII engine i want to swap, it is just the base block, would my s4 parts go rite onto the s5 motor? would i need the s5 ecu? please help, thanks

10srotary

heres what i thought i was buying a jdm 13bt supposedly with a full harness
heres what i got jdm 13bt with the wires cut about 18 inches from the fire wall
i was told i could chop and patch into the cars existing harness but not every thing is matching up is there any diagrams out there to help me the 13bt came with an N340
ecu i think it is right but no way to confirm it of the 2 plugs that dont match up on the drvers side harness im fairly sure the larger white plug with 4 wires (engine side) are from the crank angle sensor (only 3 wires on the original car harrness) im having trouble tracing the other plug back

10srotary

thanks for that i thought i was going nuts , being the only one to find an ecu in the engine bay We keep them there in the UK too never heard of anyone having much trouble with them there but i wouldnt keep my stereo there