00 S10 l31 p0300 when hot

[afuel141]

Hey guys just looking for any ideas you may have. I have a 2000 s10 l31 swap with a 0411 I have about 40 miles on it. I now have a problem with a random misfire code only when the motor gets hot it's completely fine when cold. Any ideas??? Thanks Jon

[04SilveradoMykk]

Modified? Cam, stall converter, anything? The more information the better, and at what conditions does the code set. Is it actually misfiring/running rough/shaking?

[afuel141]

Here is some more info the motor is rebuilt I did it mildly modded l31
9.8-1 comp ratio
Mildly ported Rhs heads
Lt4 hot cam
Ported intake manifold
Vmaxxx zspacer
Upgraded injector MPFI
New distributor
Egr delete
Back 2 o2 are deleted also
Not cats
Most of the sensor are new I just got another coolant temp to try
The truck is kickass when cold then very consistently missfires when hot
Didn't know if anyone has had a similar problem.
Btw it wasn't like this from the start
It does misfire big time the Ses light flashes
The truck is also a 5 speed
The code sets when the truck reaches 200* on the guage



Thanks for all the help Jon