matt566

have read and read to help with my problem but cant seem to figure it out so sorry if it answers have been posted already

the car will run but not idle very well it just jumps bounces alittle below 400 rpm
if i rev to 4 or 5 grand it dies like there is nothing there when i push the gas as well as when i put the motor under a load like in first or reverse if i try to go or rev its like the fuel cuts off. when i do rev it, its sounds like its stumbling. i havnt been able to drive it more that 10 feet. i drove it slowly from backyard to front at like 1500 or 2000 rpm and it ran fine, felt good (was level ground) but when i got to the street i gave it gas like when i was moving it (not much) it died. recrankd and rev. into driveway. now it dies when ever i put a load on it or rev high

ne suggestions

i have a 87 rx7 gxl (na - s4) put a jdm s4 turbo II motor in it used na transmission upgraded clutch. walbro 255 fuel pump rewired to fuse box to acc. 12v. (black/white wire cut pump side to fuse box, insulated otherside). turbo 2 afm. new fuel filter. new plugs. using na engine bay harness(one connected to battery) and jdm engine harness(one on motor) extended harness one by one (no mixed wires *definatly* none mixed) the boost sensor is conected to a vaccum line in the upper manifold dont see ne other line to hook it to. my boost guage is hookd up to that line and when i run the car (give gas) it go to about 20 lbs of vac but wont have boost get to almost about boost then thats when it dies around 5-0 vaccum. i have checkd and double check the afm connector and meterd it and it seems fine. it is puffing tons of white smoke but ive read and heard it was normal on first start up. the last time i started it puff alittle bit of black smoke and backfired (not at the same time) went to reverse up drive way(incline) and backfired. pulled the rest of way up driveway with truck and recrackd it still puffed white smoke. before it backfired it puffed alittle black smoke not much just little mixed in with white.

i know its alot typed but just reading these forums the more information i can provide would seem better so this is everything i can think of that ive done.

HAILERS

This sounds real similar to having the fuel injector plugs on the wrong fuel injectors.

Maybe the electrical plug for the primary is on the secondary fuel injector????? One or more places????

A fellow had the above situation on this forum once. So for fun I swapped the fuel injector wires at the ECU to mimic his problem. Let me tell you, I wouldn't even drive the car out of the driveway like that. I would start and run to some extent but ran really poorly.

This is a GUESS. It might be another thing altogether, but the wrion electrical plug on the wrong injectors will cause problems like you describe. Just a GUESS.

The injector wires are color coded and you can see the colors in the wiring diagrams in the FSM.

HAILERS

Another possibility is that the boost sensor does not have it's vacuum hose going to a vacuum source and or is not a turbo boost/pressure sensor.

A third possible is that you used a Turbo EM harness on the engine and did not make adjustments to the two large orange connectors just inside the crew compartment?????????????

All this is just GUESSING.

matt566

it is a turbo 2 boost sensor. and ive went through a service manuel to find where it goes and there is supose to be a "air control valve"? bolted on to the bottom half of the intake manifold but there isnt it has a block off plate where that is supose to be so i had that one left because there was no factory bov but a greddy "pressure release valve" was welded onto the same pipe so i put the pressure sensor in the line for the bov. or aleast i pretty sure that what i did. as far as the orange plugs under the passenger side dash i supose you are talking about the wiper, alter., and cruise control harness and the other that runs to the resistor pack for injectors. no i didnt rewire. there is also a small black plug on the jdm harness im not using.

i can only imagine what ur thinkin after reading this but here noone even knows what an rx7 looks like let alone knows nething about em. so im just jumpin into this blind. i have done several honda swaps and a couple of nissans where is was just rewire a distributor or a fuel pump.

i just printed off the ecu pin outs from a fsm and im going to just go through and rewire the whole car it seems to be my best bet.

if there are ne standard wiring swap overs from na to turbo like a wire that may need to be repind that would be helpful other than that ill just have to learn this car inside out before itll run

HAILERS

IF you have the original non turbo harness for that car, I'd suggest installing that and removing the JDM harness for sure. Just chunk that JDM harness.

We're talking USA non turbo harness and using a turbo engine. The n/a harness will work just fine. If the engine has a Twin Scroll Actuator, then there is one wire on the n;a harness that needs to be tended to, but even then it'll run just fine without that change to the n/a harness.

I can't tell you how to deal with using a JDM EM harness. It's doable but I've no experience with it. Mainly because a n/a harness will work just fine on the turbo engine.

The secondary injector wires will be routed a bit different to fit on the turbo engine. Not a big deal in any sense of the word.

NO. The boost/pressure sensor does not go where you said. It originally came off a nipple on the ACV. But you can tee it off another nipple on the intake manifold just aft of the ACV.

Decide what your going to do i.e. get a n/a harness or??????????? first.

matt566

i purchcased the car with a blown motor. was going to use the na harness but it was all sorts of cut up dont know what he was doin all i could really use on it was the wiper plug but ill just get another one i guess thanks ill give that a try. i had a feeling that what i should have done from the begining well atleast this way ive learned alittle hopfully didnt mess too much up
thanks