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Almost feels like an old dodgy carby! Idles rough as shoots fuel out the back and get even rougher if I touch the throttle and stalls. I have driven a few times when cold, if I stop instead of rolling through say a giveway sign, the car will stop and cant be started for a few mins, only then holding the throttle flat (like a carby) will it start again. Other than that any attempts earlier it'll just keep winding over and getting too much fuel. 120psi across all 6 so its getting tired but doesnt use or blow smoke.

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https://www.sau.com.au/forums/topic/449351-rough-idle-on-cold-start/
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Also to add to my other post about rough, sluggish between gear changes at times, slowly feed the loud pedal its normally ok, but mash it and grab 3rd it runs rough like its dropped a cylinder untill I back right off, let it coast then re apply the throttle

It was doing it with my stock coil packs, now ive put ls1 coils on and still doing it. .8 for the plugs. No smoke test as yet, only an issue really when cold or occasionally after a flogging. My afr gauge reads fine however I suspect the fuel pump may be a problem

Are you using a real wideband or those stupid narrowband gauges that show absolutely nothing but flashing lights.

By the way, LS coils will need more ignition dwell time to work properly. Given the fact you're using a stock ECU I am under the assumption there isn't enough spark generated

  • 3 weeks later...

45psi base. Thing is, first cold start is shit as any throttle input it runs even rougher and sometimes stalls and will crank over for about 15 seconds then fire like its flooded! Fuel pump appears to work fine as its holding 10.4 afrs at full throttle. Ive changed afm cas tps ecu fpr and still doing it. Does it occasionally between 2nd and 3rd shits where I have to back off coast for a bit and re apply throttle to run smooth again

  • 4 weeks later...

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