Big intermittent misfire, RPM reads 23000 rpm for a sec.

myastzo

Hobo restorer
Jun 6, 2011
59
0
0
35
Moscow
Hi guys!

I was trying to find out my misfire problem. Most of the times it occurs when the engine is warming up. But sometimes i get this misfire while waiting for traffic light (And sometimes it dies.)

I was trying to tune my MAFT PRO with a laptop, satisfying Vf and smoothing the VE table and seen this strange peaks of RPM, thats when the misfire goes. It peaks to 23000 RPM!!! Sometimes to 8000, and even to 3000, but the car is just warming up parked. Of course the rpm stays the same, just the signal to ECU. Sooooo. My question is: Do You guys encountered something like this?

It seems to me that the signal from igniter to ECU gets interrupted, multiplied maybe. Maybe its the wiring to MAFT PRO? But I always wire everything rock solid. And the fact that it is intermittent is against this theory.

What do you think?
 
Last edited:

myastzo

Hobo restorer
Jun 6, 2011
59
0
0
35
Moscow
I did it already, but thanks! Well I found out one of my points in VE table was 0, so i fixed it, will see tomorrow how it reacts... Strange shit...
 

myastzo

Hobo restorer
Jun 6, 2011
59
0
0
35
Moscow
Its the MAFT Pro wiring, cuz disconnecting it worked. The car idles just like a dream. If i could find the adapter from lexus AFM to K&N filter i could just remove MAFT for a whie. Nice toy, but i really starting to hate it.