having some issues

Nistune topics specific to the 6802 cpu

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bsdkllr
 

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having some issues

Post by bsdkllr »

Hello,

im having an issue that i cant seem to solve. im getting a surging/missing when im under load. mostly between the 1000 to 3000 rpm range. its an 86 z31 na it has an 86 z31 turbo auto base image on it and im not sure if that is causing an issue or if my ecu is being wonky. during warmup on some of the 86 stock images im getting a really harsh what seems like timing variation that it causing a bucking. the only thing that is not stock on the engine is the coil it is an msd blaster ss coil.

i have the logs and rom i am running and this was just a quick record driving around town.
also i did a intake leak check that came out good. and replaced MAF and Spark plugs with NGK's

1986 300zx N/A M/T
Attachments
test_2016-09-05_1257_07.csv
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9-5-12,50.bin
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Matt
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Re: having some issues

Post by Matt »

Feedback flags look strange.

Vehicle speed input disabled
Bit 6 disabled
Auto trans off enabled
Default TP/RPM scales disabled

Set these back to factory value (0x7A)

Might be responsible for using the wrong TP/RPM scales, and the Bit 6 might be causing issues (unknown flag)
bsdkllr
 

Posts: 56
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Location: Boston, MA

Re: having some issues

Post by bsdkllr »

i do have a manual transmission non turbo. so do i need the speed and auto trans on?
bsdkllr
 

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Location: Boston, MA

Re: having some issues

Post by bsdkllr »

none of that made a difference. whats weird is sometimes its better and sometimes it worse. sometimes just turning off the car and waiting a bit and starting it back up seems to make it work. yet still not quite right.

could it be a fuel delivery issue?
Matt
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Re: having some issues

Post by Matt »

So the vehicle is NA, but the board has a turbo base?

This is why the flags were different... I was comparing against 19P12 (turbo base) but that file you have posted is from 18P07 or similar (NA maps)

How come the ECU is setup for turbo but NA mapping?

What timestamps in your log are bucking?

If the vehicle is staying NA then should use NA base image...
bsdkllr
 

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Location: Boston, MA

Re: having some issues

Post by bsdkllr »

i was planning on putting a turbo in the car at some point. i wonder if there was some confusion when i ordered nistune. the bucking pretty much happens anytime i accelerate semi quickly. if i drive like i have an egg on the throttle its not as noticeable.

today i changed the spark plug wires and ignition coil. and after driving to work i do notice the engine smells like its hot. so im guessing its shooting lean during the hesitation.

it feels almost as if the maf is disconnected but not that bad.

and it is an NA ecu that is running it.
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Re: having some issues

Post by Matt »

If you are planning on turbo then this is why the turbo program was loaded

You would need a wideband controller to tell your mixtures, but usually bucking means its too lean (starving for fuel)

Load in the 19P12 (turbo maps) back into the ECU, then File > Import selected maps (from the 18P07 image) and tick fuel, timing, as well as fuel/timing scaler and K constant

See how it goes only using the basic maps
bsdkllr
 

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Re: having some issues

Post by bsdkllr »

ill give that a shot. i was playing with it yesterday and played around with fuel and timing.
fuel seemed to change nothing with the bucking but when i changed the after start timing advance from 60-110 and set it to 10deg it seems to have made it much much better. but it seems something is still not right.

i wonder if the distributor is one tooth off or a bad timing light?
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Re: having some issues

Post by Matt »

I have not played with that table, but watch your timing guage to see where timing ends up
bsdkllr
 

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Re: having some issues

Post by bsdkllr »

im going to try and get a timing light on it and check the indexing on the distributor. im also getting an rich smell while driving.
bsdkllr
 

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Re: having some issues

Post by bsdkllr »

timing was fine with the light. i think my fuel pump is on its way out.
bsdkllr
 

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Re: having some issues

Post by bsdkllr »

so fuel pump is fine. now im starting to think my ecu is faulty. previous files that ran fine are not working as intended now. and the timing keeps having blips. it will drop out for a second and return or during warmup during acceleration it will just drop down 20 or so degrees have no power until it gets to a higher rpm. nothing else is noticeably changing when the timing drops. i think i may possibly have a bad ram chip.
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Re: having some issues

Post by Matt »

Would need log files showing the issue posted here...

What if you load in the base image and then CTRL-SHIFT-Q to repair maps?
bsdkllr
 

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Location: Boston, MA

Re: having some issues

Post by bsdkllr »

i attached the latest log. ill try the repair maps. i'm guessing it needs to be connected to consult for that will work.
Attachments
NIStune_2016-11-23_0725_35.csv
(2.03 MiB) Downloaded 73 times
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