unstable rev when head lights are on after new ECU HELP!!

[dougsop]

anyone knwo why is my rev unstable??

i toke my GT4 st205 to TP to tune my power FC, after the tune i realise when ever the car come to rest the rev is unstable, it will drop below 500 and rev back up to 1100, or some times it just die. The unstable rev last for around 15-30 sec and it will go back to normal afterward.

taking the car back to TP on friday but does anyone knwo why is like that ?

cheers

[Crucible]

anyone knwo why is my rev unstable??

i toke my GT4 st205 to TP to tune my power FC, after the tune i realise when ever the car come to rest the rev is unstable, it will drop below 500 and rev back up to 1100, or some times it just die. The unstable rev last for around 15-30 sec and it will go back to normal afterward.

taking the car back to TP on friday but does anyone knwo why is like that ?

cheers

An engine will only fluctuate in revs like that if air is bypassing the throttle plate. Either being a vacuum leak, faulty stepper motor, or Aux air valve etc. Some cars are fitted with cold start idle up valves and will give these symtoms if the coolant level is low.

Check the above.

[dougsop]

thx for that.

but i realise the real problem was that TP drain my battery while they where doing dyno

they car battery was running very low, so it was unstable, specially when i have those 8000K lights on at night .

is getting better now after a day of driving around

but thx for the info

[dougsop]

ok. it is not the problem with the battery.

the unstable rev continue.

unstable rev occur when the head lights are switched on. (tested for both factory and aftermarket headlight).
car run fine during the day when the lights are not on, but once lights are switch on rev drop below 500.
the funny thing is that it will only happen when the light switch is turn on and not when i keep the flashing high beam on.

so does that mean something to do with the switch and ecu ?

help plz ?

anyone know why ?

[ezy10s]

i dunno if the power fc has this function but i know a couple aftermarket ecus have a voltage clamp function, which will stop the power being sapped too much when electrical loads are turned up aka lights on , stereo on, etc. if your ecu does have this it may not have being set correctly(if at all) or your ecu may not have provision for this tyrpe of adjustment.

[ROBODISCO_20v]

Install an earthing kit & voltage stabiliser, it will help.

http://www.trademe.co.nz/Trade-Me-Motor ... 371034.htm

[Alex B]

Do you have any proof of that or are you talking out your ass? If you have suffecent earthing that will do sweet $&#$% all.

[RedMist]

anyone knwo why is my rev unstable??

i toke my GT4 st205 to TP to tune my power FC, after the tune i realise when ever the car come to rest the rev is unstable, it will drop below 500 and rev back up to 1100, or some times it just die. The unstable rev last for around 15-30 sec and it will go back to normal afterward.

taking the car back to TP on friday but does anyone knwo why is like that ?

cheers

An engine will only fluctuate in revs like that if air is bypassing the throttle plate. Either being a vacuum leak, faulty stepper motor, or Aux air valve etc. Some cars are fitted with cold start idle up valves and will give these symtoms if the coolant level is low.

Check the above.

I ditto, CHECK THE ABOVE.

[fivebob]

Also check the ignition map in the idle zones. It should be constant over the entire idle range. If it varies it can affect the idle stability.

[ROBODISCO_20v]

Do you have any proof of that or are you talking out your ass? If you have suffecent earthing that will do sweet $&#$% all.

http://nzhondas.com/phpBB2/grounding-wi ... highlight=

[fangsport]

anyone knwo why is my rev unstable??

i toke my GT4 st205 to TP to tune my power FC, after the tune i realise when ever the car come to rest the rev is unstable, it will drop below 500 and rev back up to 1100, or some times it just die. The unstable rev last for around 15-30 sec and it will go back to normal afterward.

taking the car back to TP on friday but does anyone knwo why is like that ?

cheers

An engine will only fluctuate in revs like that if air is bypassing the throttle plate. Either being a vacuum leak, faulty stepper motor, or Aux air valve etc. Some cars are fitted with cold start idle up valves and will give these symtoms if the coolant level is low.

Check the above.

I ditto, CHECK THE ABOVE.

or connections to them.

Do you have any proof of that or are you talking out your ass? If you have suffecent earthing that will do sweet $&#$% all.

http://nzhondas.com/phpBB2/grounding-wi ... highlight=

Robodisco, quoting that link, has merely exposed a weakness of yours.

an earthing kit will be an improvement if your existing earth points are shite.....................or you are after some bling.

[Alex B]

Thanks for proving my point by posting that thred

[fangsport]

Thanks for proving my point by posting that thred

don't get me wrong. earth is vital.........but blinging your engine bay with fancy neon looking wire will only be of use if the factory earth points arn't doing their job.
it is far cheaper(albiet, less bling), to cure the initial problem, than to spend drug money on crap that may work, but dosn't fix the initial prpoblem.

[dougsop]

already have bling bling earthing kit.

i guess is the idle on the power FC that is not set probably, and it should be tweakable. taking it back to TP tomorrow and see how it goes.

[ROBODISCO_20v]

My comment about the earthing kit was in reguards to this:

ok. it is not the problem with the battery.
the unstable rev continue.
unstable rev occur when the head lights are switched on. (tested for both factory and aftermarket headlight).
car run fine during the day when the lights are not on, but once lights are switch on rev drop below 500.
the funny thing is that it wll only happen when the light switch is turn on and not when i keep the flashing high beam on.
so does that mean something to do with the switch and ecu ? anyone know why ?

No factory earths are adequate when you start modifying.
My levin had two crapy thin wires for the earth from factory. After I install an earthing kit my digital volt meter in my SAFCII never drops below 14.2v, with the factory earth it would drop right down into the 13s. I think I even saw it drop into the 12s once. I know its not a huge difference but at least I know my stero, head lights, ignition etc are getting the max voltage available to them

[dougsop]

problem now solved by TP

it was the problem with the idel setting in the engine bay, they need to adjust that to match the PFC