RPM signal only when cold

[ChachiS13]

Heres my setup:

1990 240SX with SOHC ClusterBlacktop SR with E5 ECUApexi AVC-R

Ok, installed my AVC-R and it will only read RPM's when car is first started. Before my instalation of the AVC-R I have never had a way of reading RPMs in my car so I dont know if the problem is new

Once car is at operating temp, the RPMs start flickering random numbers until it eventually just reads 0 RPM

If I shut car off and let it cool off for a sec, it will start reading again then shut off after a couple seconds. So Ive come to the conclusion that this happens when something gets heated.

Any ideas?

[s13sr20chris]

i would venture a guess that its either the crank angle sensor or the ignitor. try getting her hot and rpms messing up then spray one component at a time with brakeclean spray. if they come back thats your prob.