What I have is...

Black wire with white stripe.
Brown Wire with Red stripe.
Brown wire with white stripe.
Brown wire with black stripe.

 

The car started out as a '86 n/a then had a full '87 TII swap done using a JDM TII harness that was re-pinned.

I looked over the NZCONVERTIBLE posts but I'm having trouble pinpointing my problem still. Was going to try adding a ground.

 

I'd go get a meter out and go to the boost sensor. Unbolt it and turn it up where you can backprobe the BROWN/RED wire with the meter. Leave the plugs all connected up. See if when the key is ON whether or not you have approx 2.7 vdc give or take a touch.

Deja vu all over again.

 

Seems to be a pretty common problem.

 

I added a ground at the boost sensor but it didn't help any. Under load, the car will accelerate, but it stutters and bucks quite harshly.

 

Using a JDM ECU?

 

No. I tried 2 different JDM ECU's with no luck, so I'm using an N333 USDM as of today.

However I am using a TII EM harness.

 

You do know abouit fuel cut don't you? If the boost is too high on a stk turbo the ECU will cut the fuel to a rotor to protect the motor. That's why they make fuel cut defenders.

You probably know, but just in case I wrote that above. I think boost over eight psi will cause fuel cut.

 

Yeah, I know about fuel cut, but I don't think it would be building 8psi by 3500rpm would it? I'll take it out again today and watch the boost.

 

I'd go look at the volts dc on the brown/red wire in the boost sensor with the connector on the sensor. Key to ON. See if your reading reads like the manual. I THINK it's 2.5 to 2.7 dc with key ON engien OFF.

Fuel cut happens when the sensor outputs???? Ive forgotten the exact figure. I believe 3.65 vdc. The wrong sensor for your car might output this high a volage waaay too soooon. Possibility. NOt a big possible but possible.

 

I checked the boost sensor and it reads 2.4 DCV.

I added the ground at the boost sensor, and zeroed in my TPS.

I took it around the block, and the bucking is less severe, although it may be impart to the car now hitting a brick wall when the secondary injectors are supposed to kick on.

Where would I start troubleshooting the infamous secondary injector hesitation?

 

I came across https://www.rx7club.com/showthread.p...rpm+hesitation

I pulled my hose off my boost sensor and plugged it, then unplugged my TPS. (to try and simulate load) I hope I did it right.

When I did that, the car revved rather normal. There was a slight hesitation at 3500, but a little more throttle pushed the RPMs right along.

Where should I go from here?