Saturday, October 25, 2008 - 03:48 pm, by: Scott Wilkes(Scottywilkes)
ok, got the car a week ago, everything is going great, yesterday i went to get lunch from work, came back, shut it off and went back to work, when i started it back up at the end of the day, instead of starting and sitting on 12-1500 on choke, it dropped straight down to 600 revs, even when off choke before it would idle at 7-800 revs.
I removed the idle speed motor and cleaned it out, pulled the plugs to make sure the coils and plugs are ok, but none of that made a difference. Any idea what it could be causing this? As it did it so suddenly.
Also if u tap the throttle when its idling, it hicups a bit and then takes off.
Car runs beautifully, in boost, out of boost etc, has the same power as before, just idles really low. Thanks
Saturday, October 25, 2008 - 09:48 pm, by: Scott Wilkes(Scottywilkes)
yeah i reset the ECU, u can do that via unhooking the battery for a while yeah? I had the battery out for about 20 mins while to get to some other bits. It hasnt effected the driving of the car at all, its just it dosnt go into choke when cold and is very rough at idling, dosnt stall though.
Im assuming the throttle position sensor is the black adjustable sensor opposite where the throttle cable pivots the throttle body plate?
Sunday, October 26, 2008 - 11:10 am, by: Cihan Aday(Cihan)
Auto choke?
When the throttle position signal is registering that your foot is coming off the accelerator, the Idle Speed Controller (a stepper motor) opens an airway to the intake manifold (bypassing the throttle body) and is modulated by the ECU to maintain a steady idle.
To 'auto-choke', the ECU relies on the same principal but elevates engine RPM, pulls a few degrees ignition advance and enriches the fuel mixture.
To diagnose, you need to check the TPS resistance & output voltage (as mentioned) and disassemble then clean the ISCV (idle speed control valve). A lot of the time the cause is related to these items, but on the odd occasion it resides within the ECU itself.
Sunday, October 26, 2008 - 11:55 am, by: Scott Wilkes(Scottywilkes)
yeah ive taken the ISCV out and cleaned it out, it was quite clean, sprayed it out with carby cleaner, and it came out rather clean, did that, blew it out and reinstalled it, but that didnt help, ive got the TPS out now,
Would u be able to tell me how to check output voltage? Im guessing it has to be hooked up to do that otherwise there wouldnt be any input voltage HAHA.
Also anyone got the specs of resitance at part, full and idle positions. Or is there a guide on here anywhere? Thanks