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Strange Idle When Lights Are On!

J34

By J34,
in Engines & Forced Induction

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J34 Proficient

J34

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Posted (edited)

Hi all just got a wierd problem I've got a power FC on my R34 now all of a sudden when i start my car it idles fine then when i turn the lights on it revs to 1500rpm then drops to 1000rpm then goes back to 1500rpm and repeats over and over then when i turn the lights off it goes back to normal. :P Anyone have any ideas my BOV is set to full plumb back im going to try putting the standard one on tomorrow and see how it goes I also think it might be the AAC valve. Anyone have any ideas???

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Al Grand Master

Al

Posted
Posted

Not sure if Pfc's have "voltage compensation", but if they do, this needs to be tuned.

Either way this sounds like a tunning issue; take the car back to your tunner and ask him to ajust the tune accordingly. It could be a 2min job.

JustinP Mentor

JustinP

Posted
Posted
Hi all just got a wierd problem I've got a power FC on my R34 now all of a sudden when i start my car it idles fine then when i turn the lights on it revs to 1500rpm then drops to 1000rpm then goes back to 1500rpm and repeats over and over then when i turn the lights off it goes back to normal. :pirate: Anyone have any ideas my BOV is set to full plumb back im going to try putting the standard one on tomorrow and see how it goes I also think it might be the AAC valve. Anyone have any ideas???

Re-run the 30 minute idle learning procedure - this should fix it.

J34 Proficient

J34

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As far as i know to get to the idle reset requires the tune to be wipe the whole tune which i really dont want to do. I just put my stock BOV back on and cleaned the AAC valve it now idles better than ever untill I turn the lights on then its the same problem Anyone know of any Power FC Tuners close to Northern Sydney/ Northern beaches???

enzan Explorer

enzan

Posted
Posted

Hmm, I don't know anything about the PFC or how it's wired in etc. But if it were me I'd be starting with the basics, make sure the battery terminals are clean and tight, check alternator charge rate with the head lights on and off and check all earth connections. That's how I'd approach this.

700HP-GTR33 Mentor

700HP-GTR33

Posted
Posted

It might be your AFM.......give it a dust out...while you are at it clean your filter/

This sometimes can cause your problem.

It seems to me like a air/fuel problem...you said it just started to happen....so your tune might be fine.

My nephews car use to cut out on him...until he re-soldered and cleaned his AFM's.

Could also be your injectors...put some injector cleaner in your tank.

Good luck finding your fault.

J34 Proficient

J34

Posted
  • Author
Posted

Well I drove the car to Unique auto sports today and was fixed in about a minute. Some adjustment in the idle control on the PowerFC seemed to have fixed it up :sorcerer: So free plug for UAS! :stupid:

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