Jumper in wrong spot s13 ka24det, z32 MAF q.

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EnnEssEnnKAT
 

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Joined: Fri Mar 10, 2017 6:40 am

Jumper in wrong spot s13 ka24det, z32 MAF q.

Post by EnnEssEnnKAT »

92 s13 ka24de

Hey guys just got my ka-t running but not very well. I pulled the ecu and looked at the nistune (ecu and type 3 board purchased used) and saw the jumper was in the stock ecu spot (cj1) instead of the spot to use the nistune board (cj2). I know i just need to change this over but thought that was strange. Any ideas on why one might do this?

Second, i wired up my z32 maf according to the jim wolf instructions where the two grounds "C" and "D" are grounded. but found in the nistune guide under z32 maf to not connect one of the grounds. Is that specific to a z32 chassis or for when a z32 maf is used with nistune in general (such as on my s13)?

Wire A - N/C
Wire B - Signal (shielded white)
Wire C - 12v Hotwire Ground (black) [Not used - do not connect]
Wire D - Signal Ground (shielded black)
Wire E - 12v Power (white)
Wire F - N/C


Thanks!
EnnEssEnnKAT
 

Posts: 16
Joined: Fri Mar 10, 2017 6:40 am

Re: Jumper in wrong spot s13 ka24det, z32 MAF q.

Post by EnnEssEnnKAT »

Update:

I was able to connect the PC program after swapping the jumper to the ECU and downloaded/saved the tune file from there. I compared it quickly to the s13 ka24de stock ROM tune and they are different but not unrecognizably different. MAF is set to z32 so that's a check, timing fuel etc all looked a little different than stock so i feel good about the tune. However i am still having trouble starting so I dug further.

I did find two pretty major issues and one is the ignition/dash lights will all remain active after i have removed the key. Swapping in my spare stock ECU i had does not have this issue. A quick Google suggests the ECU is bad so i opened it up...

Found a fried/burned open trace leading to pin 36 which is related to the ignition coil. I am positive it was like this when i bought it judging by the physical condition (poor) and the incorrect jumper position. Probably need to swap the nistune hardware to my other ECU now. Is it likely the nistune board is still OK since i can read from it?

Thanks if you kept up so far!
colby45
 

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Joined: Tue Jul 11, 2017 8:25 pm

Re: Jumper in wrong spot s13 ka24det, z32 MAF q.

Post by colby45 »

Good findings on the wrong jumper and the issues. Hope those got resolved soon.
Matt
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Re: Jumper in wrong spot s13 ka24det, z32 MAF q.

Post by Matt »

ECU has a hardware issue. You need to repair the track, remove the old diode and replace with another one. Reisstor might also need replacing

Either that or change over the ECU for another one and reinstall the board (which appears fine)
EnnEssEnnKAT
 

Posts: 16
Joined: Fri Mar 10, 2017 6:40 am

Re: Jumper in wrong spot s13 ka24det, z32 MAF q.

Post by EnnEssEnnKAT »

Thanks for the input, what I ended up doing was swapping the nistune type 3 to my known good ecu, and am starting with that. It definitely starts the car better!
Matt
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Re: Jumper in wrong spot s13 ka24det, z32 MAF q.

Post by Matt »

I see it often on all different Nissan ECUs.... I think people feed devices off the ignition wire which draws reverse current and kills the diode (and track)
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