So what method are you using for RPM ? Not the alt then ?
MAP ok, generally they are plastic - occassionaly the mounting tabs has metal rings which are connected to the GND....
Is the TPS on the throttle lever ?
Have you buzzed that to see if the GND on the pot isn't connected to the case ?
It's good practise to use the power and ground from the engine for the ECU or sensors etc generally speaking.
In simplystic terms, it's like hunting for a ground loop with a stereo amp. 1/5th of it is magic.
So run power and GND from the engine.
For the level and frequency that the sensor operates at the differential between the chassis and the engine could be substantial.
Your mileage and that of others may vary.
What are you using for the PSU on the setup ?
Do you have a sinlge drop regulator or multiples ? 7805 ?
Smoothing caps ?
MAP ok, generally they are plastic - occassionaly the mounting tabs has metal rings which are connected to the GND....
Is the TPS on the throttle lever ?
Have you buzzed that to see if the GND on the pot isn't connected to the case ?
It's good practise to use the power and ground from the engine for the ECU or sensors etc generally speaking.
In simplystic terms, it's like hunting for a ground loop with a stereo amp. 1/5th of it is magic.
So run power and GND from the engine.
For the level and frequency that the sensor operates at the differential between the chassis and the engine could be substantial.
Your mileage and that of others may vary.
What are you using for the PSU on the setup ?
Do you have a sinlge drop regulator or multiples ? 7805 ?
Smoothing caps ?