R33 Gtst Running Rough Using Lights/windows Etc

[KerrodR33]

My '96 R33 gtst has recently started to run really rough when using headlights or winding the windows up or down.

At idle if the headlights are turned on or the brake pedal pressed the idle starts to hunt and when taking off it coughs and splutters like it's choking.

I have played with all the usual electronics and have found most cause the idle to hunt before regathering itself or if it's the headlights to constantly hunt and then intermittently run like ass.

Occasionally it will stall when coming to a stop using the brakes and clutching in. While cruising at say 80km/h and I wind the windows up or down or turn the headlights on it will splutter briefly until I stop using them.

I have used a multimeter to test everything and the battery is holding charge and not dropping in volts when the electronics are used so I am very confused. Also I have removed the IAC valve and cleaned it to see if that would help but that failed. It has brand new coilpacks and spark plugs gapped to .8mm and I am running an adaptronic ecu with map sensor.

Any ideas?

[SkudR33]

My '96 R33 gtst has recently started to run really rough when using headlights or winding the windows up or down.

At idle if the headlights are turned on or the brake pedal pressed the idle starts to hunt and when taking off it coughs and splutters like it's choking.

I have played with all the usual electronics and have found most cause the idle to hunt before regathering itself or if it's the headlights to constantly hunt and then intermittently run like ass.

Occasionally it will stall when coming to a stop using the brakes and clutching in. While cruising at say 80km/h and I wind the windows up or down or turn the headlights on it will splutter briefly until I stop using them.

I have used a multimeter to test everything and the battery is holding charge and not dropping in volts when the electronics are used so I am very confused. Also I have removed the IAC valve and cleaned it to see if that would help but that failed. It has brand new coilpacks and spark plugs gapped to .8mm and I am running an adaptronic ecu with map sensor.

Any ideas?

Quick fix is to raise your idle a bit.

I'm sure somebody else has experienced this...

[KerrodR33]

That might work however it would still run rough as shit in lower rpms as it is now wouldn't it?

Edit: Just read my first post and I think I forgot too mention that while cruising or in the lower rpm range not making boost it coughs and misses as well. It runs really rough until I start bringing it onto boost and then gear changes it feels like it loses all momentum similar to applying brakes a bit.

This only happens when using headlights or windows. So during the day it runs completely fine

Edited August 14, 2014 by KerrodR33

[SkudR33]

That might work however it would still run rough as shit in lower rpms as it is now wouldn't it?

Edit: Just read my first post and I think I forgot too mention that while cruising or in the lower rpm range not making boost it coughs and misses as well. It runs really rough until I start bringing it onto boost and then gear changes it feels like it loses all momentum similar to applying brakes a bit.

This only happens when using headlights or windows. So during the day it runs completely fine

Have you checked ignition, fuel and air to make sure there is no issues?

If you want a walk through guide of what you need to do, I'll be more than happy to spend 10 minutes writing up a little guide. But I think you might be able to find some threads relating to similar issues.

[KerrodR33]

Well as far as fuel and ignition goes it has brand new injectors, fuel pump and fuel filter and brand new plugs and splitfire coil packs installed about 2000km ago and new tune and all was working fine up until about 2 weeks ago. Checked for leaks and vaccuum leaks and haven't found any.

It really has only started happening since I replaced the alternator and didn't have any problems at first so maybe something wrong with that?

Although it's charging the battery fine and when I turn the headlights on there is no drop in voltage on a multimeter, only the noticeble changes in idle and driving behavior.

[scotty nm35]

Sounds like the injector voltage offset is set wrong, the injectors take longer to open as the voltage drops. It would be a simple tweak for your tuner to sort out I assume.

[SkudR33]

I once had this major problem with a misfire. I had installed brand new injectors a month earlier, they turned out to be faulty. You can't rule out brand new parts

[SkudR33]

Also check your earth wiring, specially the one from the motor to the chassis

[XGTRX]

Agreed. If it's electrical related check the earths, battery, engine, igniter and cas. Clean, sand and remount. Start here before you touch anything, especially if anything was played with from when the problem started.

[KerrodR33]

Cheers guys will have a look tomorrow and see if I can rule anything out.

And Scotty is there a way to check the Injectors with out taking it back to my tuner for this drop?

Edited August 15, 2014 by KerrodR33

[SkudR33]

Cheers guys will have a look tomorrow and see if I can rule anything out.

And Scotty is there a way to check the Injectors with out taking it back to my tuner for this drop?

Goto to the last few posts on the thread I linked below. I wrote up a small guideline to check injectors because that turned out to be my issue.

http://www.skylinesaustralia.com/forums/index.php?/topic/438150-Cylinder-%231-Dropping-Completely

[skylinecouple]

Have you installed a Z32 AFM ? If so, some people earth it to the chassis near the AFM. Try connecting the two centre wires of the Z32 AFM together then connect that to the white/blue wire of your wiring harness. Obviously it is connected and running now but apparently with one of the AFM wires connected to the body it can cause bad running. See tutorial.

[Dose Pipe Sutututu]

Let me guess, you're running an Adaptronic?

You need to set the base idle duty cycle too and set the dwell correctly vs. voltages or else you'll get all sorts of issues.

Also I find allowing up to 3 degrees of variable ignition timing on the idle close loop helps with all those issues

[KerrodR33]

Let me guess, you're running an Adaptronic?

Yep lol I will mention this to the tuner and see if he can sort it out

Cheers

Edit: Also is it bad to drive the car when it runs into these issues? Currently on my corporal course for work and can't get to the tuner for a couple of weeks

Edited August 18, 2014 by KerrodR33