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#62212
Hey,

I really need some help rn. I recently overhauled my nb miata 1.6 engine. I installed new con rods and piston rings. After putting all back together the engine ran really good, good compression etc. Today i wanted to go on a drive and after driving maybe 1km the engine suddenly had no power and stalled. When trying to start it again it vibrated a lot and ran very rough and only when i gave it some throttle. I then got towed back home. Now im troubleshooting, i can control every injector and spark plug via the testing page, i did a composite and tooth log, maybe someone can help me, i'm really frustated rn :(((

here's a video how its running https://photos.app.goo.gl/dsXexKJPuQ6zPzDcA
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#62218
which cylinder? what pressure did it make?
from the video it looks like cyl 1 is running OK and the others not.
I don't understand what you mean about losing compression in 10 seconds. It's not surprising to lose compression on cylinders with holed pistons as soon as the holes appear.

out of interest, what do all those programmable outputs do?
#62219
jonbill wrote: Sat Apr 01, 2023 5:37 pm which cylinder? what pressure did it make?
from the video it looks like cyl 1 is running OK and the others not.
I don't understand what you mean about losing compression in 10 seconds. It's not surprising to lose compression on cylinders with holed pistons as soon as the holes appear.
out of interest, what do all those programmable outputs do?
I think i tested cyl 2 because i thought cyl 1 was fine and the others not, just as you wrote. I think it was 10 or 12 bar even though I know that my gauge almost always reads very low, so that should be fine. The engine problems started really suddenly like in a time frame of 10 secs, that's what i meant. I actually only set up 1 programmable output but i just now saw that all of them are configured, maybe that was the problem. I disabled all of them now and will try again tomorrow. What do you mean by holed pistons?
#62221
If those odd programmable outputs have appeared on their own, I'd run an eeprom-clear before reloading the tune.
Re piston holes: I mean mechanical failures happen when they happen, and with a new built engine I'd be thinking about that too.
If eeprom-clear and reloading the tune dont fix it, I'd compression test all 4.
#62223
FiatDuino wrote: Sat Apr 01, 2023 6:21 pm Do you have a datalog from when the engine was running ok and another datalog of this rough running?
The composite log looks good.
yes. While datalogging the rough running i think i also pulled plug wires so at some times it might be even worse.
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