J Rolfe

Thank you to everyone that helped. It ended up being a issue with the sensor.

The sensor was originally grounded through the ecu sensor ground but for testing purposes it’s now grounded to the chassis/engine

Sensor is still reading weird values after driving vehicle. Jiggled around the connectors at the sensor side and the ecu side to no change. Grounded the sensor directly to the battery but did not change anything. Gently blew out the sensor port but also did not change anything as well as looked into the port and didnt see anything. Checked there is 5v at the sensor connecter and there is. No blockage into the intake manifold.

Dont know yet. Ill take the car for a drive when I finish work and see.

This is the log file after swapping ground points. From what I can see when the engine is first cranked the MAP voltage doesnt seem to fluctuate as much as the screenshot you sent me. Am i right? PC Datalog - 2023-11-8 12;16;37 pm.llgx

We suspected a grounding issue with it so instead of it grounding from the ecu originally it is now grounded directly to the chassis. Ill move the ground to the engine block to see if that makes a difference and will check the connections are secure in the connector

The sensor has done about 50km. Do you suggest I order a new one? Before that ill try blowing out the sensor and seeing if there is something in it.

No, but It looks like it might go back up to 100kpa a little faster. If i blow into the hose while its connected to the sensor it will go up like usual so it is reading.

Here is a log file of the car faulting. Will try start but wont idle. Yes it is that sensor that I am using PC Datalog - 2023-11-8 7;37;43 am.llgx

PC Datalog - 2023-11-7 8;16;44 pm.llgx

Interested to see if anyone else has run into the same issue. I have a external link 3 bar map sensor into a G4X Fury in a R32 Skyline GTST. The sensor will read within ±5kpa of 100kpa when the engine is not running and when warming up will stay within that value. If I go for a drive and get the engine up to operating temperature then turn it off and on again the car will not start and the map sensor will read way out of value, eg 14.3kpa and will slowly go back up to 100kpa. Sensor is mounted next to brake master. Screenshot attached is after a drive

I have selected the wasted spark option as I have two coils (coil 1 controlling cylinder 1 and 4 and coil 2 controlling 2 and 3.) When i use the ignition test to test spark on ignition 1 and ignition 2, there is strong spark. If I crank the engine, there is spark on ignition 1 but none on ignition 2. When I stop cranking there will be a pulse of sparks from ignition 2. We have tested the igniter and coils. The spark plugs are good. Does anyone know what's going on?