z31 Connection Issues

[Rudster]

I've been having some issues with Nistune installed on my 86 z31 NA. I did the install myself, and initially it worked fine. I could connect to the Nistune board, make adjustments, the car ran, etc. The car is not currently driving on the road, so my only changes were related to idle and trying to get it to run half decent around the parking lot.

Anyways, I started to encounter inconsistent issues with Nistune after running the car for a bit. For example, sometimes when I would make a change to the K value, the engine wouldn't respond, although Nistune indicated that the change "took" (ie. registered the new K value in the software). Other times, the engine would respond as expected and my AFRs would change accordingly.

Most recently, I tried running a bin from an 87 turbo. Initially, all the maps uploaded, but the car was running extremely rich. So, I tried to adjust my K and latency values back to when I had the car running OK. Much like earlier, however, the changes I was making on screen were having no effect on the engine. I had tried to lean out the mixture to get the car to run, to no avail.

Anyways, after attempting to start the car unsuccessfully, the fuel pump started pulsing on and off, the diagnostic LEDs stay lit full time, the car won't run, and I can't connect to consult. I bought another [used] ECU and it behaved normally. Couldn't get the car to run, but I'm pretty sure that's because my plugs are fouled and the engine's full of fuel. I then transplanted the Nistune board over to the new ECU, only to encounter the same fuel pump pulsating and lack of Nistune consult. With the factory 28-pin chip installed, the fuel pump and LEDs function as normal.

I'm stumped. I suspect my issue is with the Nistune daughterboard itself, as I cannot connect to consult at all (as I say, I could before).

What things can I test? Should I send a diagnostic log from Nistune when I try and connect to consult?

[Matt]

Where are you located? If in the USA, contact Andy @ AutovaughnPeformance (see workshop listings).

Sounds like along the line somewhere the ECU program got corrupted (and then that was burned into the board). Now the corruption is permanent. Corruption is not a common occurrence, but if there is something causing it (like electrical issues or interference) then that is why it has happened

Try a board reflash and see how that goes

[Rudster]

Okay, that's what I figured happened. I'm in Canada (Ontario), but near the border. I'll get in touch with Andy (I ordered everything through him) about getting it reflashed.

I'll update this thread with any relevant information I come up with.

Thanks!