R34 Gtt Misfiring And Backfiring

[lukea87]

I recently bought a rb25det neo engine from a importer and droped it in my r34 gtt that i bought with no engine, I started the engine last weekend and the engine runs well but on cold starts now it has trouble to idle and is real rough but then it straightens out after a bit and idles fine,

at roughly 1200-1500 rpm it misfires and backfires, I checked the ecu faults and its brining up code 21(ignition signal) and 34(knock sensor)

I have replaced spark plugs with ngk bkr6eya-11 and have cheched each idevidual coil pack with the car running and they seem to be working fine.

one of the plugs leading off the throttle body (in the picture) I dont have a plug on my loom to connect to it and im not sure what it is?

If anyone has any advice as to why it could be misfiring or what the plug is that would be great

[Ben C34]

That plug goes to the TPS,cant you folow the wires back to it?

There are 2 plugs that go there, not sure why, maybe something to with traction control.

[lukea87]

I have followed the wires back and checked the loom but there is nothing there, I thought mabey the previous owner had cut it or something but cant find no other wire or plug that would go there.

[StevenCJR31]

the second tps plug is for the auto trans

[lukea87]

the second tps plug is for the auto trans

nice thanks mate... forgot to add the engine was of a auto

[Ben C34]

ahh.. that makes sense!