PDA

View Full Version : KA24DET Missing at 3500 only when warm


jmizell2
01-30-2007, 06:56 PM
I have a 1990 s13 with a 98 ka motor recently turbocharged. T3T4 intercooled 550 injectors high flow fuel pump cams enthalpy ecu.

When the engine is cool and not quite warmed up it runs great pulls hard up to about 6800 rpm no miss no bogging quick spoolin to 1 bar.

Once the motor warms up when I accelerate the engine hits the wall at 3500 rpm and starts missfiring and will not pull past that point. If I put the clutch in it will rev no problem to red line. I have changed the plugs from iridium to ngk platnum gapped at .025, new ngk plug wires and a msd blaster ss coil no change. The old plugs all were a nice grey color when I pulled them. Static timing is at 18 degrees BTDC.

I am thinking that the engine timing and fuel maps are different for start up verses fully warmed up but need some clues as to which direction to go next.

Any help would be appreciated.

bongnak
01-30-2007, 07:05 PM
what maf are you running, prob a z32 right usually when you cant rev past 3500 your ecu isnt recieving a maf signal. check wiring to maf

jmizell2
01-30-2007, 07:15 PM
Maf is a z32 but why would it run so well when cold then start missing when warm?

Flybert
01-30-2007, 09:40 PM
It's not the MAFS. MAFS problems cut out the car at 2500RPM.

Since it has to do with the car being warm, it could have to do with the coolant temp sensor being faulty.