cheesecow1

So it's been quite a while since I've had my MSPNP installed in a miata but I recently re-swapped my motor and re-installed it. I have the same setup I had about 2 years ago a 94 1.8 motor in a 91 miata on the 91's wiring harness with a 90-93 MSPNP. The car is running well, good idle, nice afr's for the most part. However I am having issue with the car when I am barely on the throttle. Once the car warms up 160+ it gets really wonky when I am at any rpm and lightly on the throttle. It jumps erratically like the spark or fuel is cutting out not quite sure what is going on. I've included a datalog of it occuring and my tune. Any suggestions would be appreciated!

GregTSi

iTrader: (1)

Mine does the same thing, but it clears up above 2.5k rpms and only does it sometimes.

cheesecow1

I'm thinking maybe my TPS is just really touchy/dirty when I'm barely on it. Could you post a datalog & msq of yours doing it Greg, maybe it'd help if I have something to compare mine to as well.

cat10

hi there, did you sort this problem out?

I have exactly the same problem, not sure what it could be....nothing shows up on the datalog.

Cheers

Braineack

iTrader: (62)

under basic settings > engine constants. Change injector staging to alternating.

richyvrlimited

iTrader: (1)

As brain said, and then have fun re-tuning completely

How did that get set to simultaneous?

cat10

Umm, maybe not quite the same problem for me then....I had my injector staging set to alternating.

My car has a random stumble which is normally below boost levels, my tune other than that is quite good.
I have used Tunerstudio autotune to tune and my afr,s are good in and out of boost.....just got this jerky stumble to sort out and thats about it.

By the way I have changed the plugs,leads and coils.

Cheers

fooger03

iTrader: (2)

check your idle voltage - the replacement engine may have an alternator going out. Hesitation at low RPM, esp. low throttle, is a symptom of low voltage. Any difference with headlights on? What about when you turn on your A/C as well (which turns on both radiator fans by default)?