Revving funny when cold

[93MX3SpecialEdition]

I recently swapped in a KL-ZE into my car. I have the 1.8 manifold on it and it is running on the K8 ECU.

The problem I am having is that it will start to really stumble and hesitate at about 2500 to 4500 rpm. This happens more when it is cold and once it is warmed up it seems to be better, but still hesitates up in the RPMs.

Just looking for some insight into this problem!

[kp2t]

i had that too... it went away when I got the curve neck manifold

[jschrauwen]

I recently swapped in a KL-ZE into my car. I have the 1.8 manifold on it and it is running on the K8 ECU.

The problem I am having is that it will start to really stumble and hesitate at about 2500 to 4500 rpm. This happens more when it is cold and once it is warmed up it seems to be better, but still hesitates up in the RPMs.

Just looking for some insight into this problem!

It would be unrealistic to expect a smooth and problem-fee running engine when ther's a missmatch in parts put together. Running a K8 Im and ECU on a ZE is only for interim measures if one could not afford the complete Eunos 800 engine and IM w/ TB and the corect ECU and VAF configuration to compliment the entire set-up. As kp2t mentioned, this should all go away once you have the correct engine parts matched with each other.