High Idle right after 5 speed swap - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

vegita319 · 04-01-2005, 12:30 AM

Ok I did a search and came on this thread about the guy car's running rich. He was idling high and tried replacing iacv, rotors, caps, plugs, wires, fuel filter and so on. I did the same stuff and i even adjusted the idle and the lowest it would go is 1000. I was trying a bunch of things and all of a sudden, when i unplug my EFI harness, the idles drops normal and i can adjust the screw to get 700 rpms.

The only problem is when i plug the efi harness back, it shoots back up to 1500. I dunno if its my IACV or not but adjust the screw does make a difference. That leads me to think its fine. It's been idling high after the 5 speed swap and I have searched and no one else that has done the swap had high idle for the ka.

I checked all the hoses for vacuum leaks, and I've checked the timing as well. I'm pretty much out of ideas. Ctune has looked at it as well and they are stumped! So any other suggestions would be helpful.

Edit- O yeah, I already pulled codes and it shows 55, meaning everything runs fine.

the head · 04-01-2005, 08:22 AM

sounds like your IACV is stuck open claen that bich out with some carb cleaner probably just carboned up and stuck

**Phlip** · 04-01-2005, 09:01 AM

Are you still using the auto ECU? If so that is your problem, get used to it or get a manual ECU
http://www.zilvia.net/f/showthread.php?t=74615

drift freaq · 04-01-2005, 10:17 AM

normal auto ecu stuff, but if you go to the 5 speed ecu you will lose a few cool things.
The auto ecu on a S13 is actually a secret weapon performance upgrade. Ya you get the funny drop to idle issue but the trade off is no speed cut!! Higher rev limit 7200 and a better curve . Yes a better curve!! Why because auto trannys are much different than clutch manual setups . So the ecu maps have a different curve to them. All the auto cars I have swapped have always been quicker useing the auto ecu. vs a 5 speed ecu car.

**Phlip** · 04-01-2005, 09:42 PM

Damn, makes me angry that my auto ECU was for a single cam and my engine is a twincam

vegita319 · 04-02-2005, 05:10 PM

Quote:

Originally Posted by PHLIP

Damn, makes me angry that my auto ECU was for a single cam and my engine is a twincam

Well, I have a twin cam ecu and the engine is a twin cam, and it still idles funny like that, so you're probably not missing out on much. I have to admit though, the car does feel faster and gets better gas milage on the highway compared to my twin cam 5 speed. It just sucks around the streets because the high idle is causing my car to get around 12 mpg.

04-01-2005, 12:30 AM	#1
vegita319 Zilvia Junkie Join Date: Aug 2004 Location: Long Beach, CA Age: 39 Posts: 460 Trader Rating: (1) Feedback Score: 1 reviews	High Idle right after 5 speed swap Ok I did a search and came on this thread about the guy car's running rich. He was idling high and tried replacing iacv, rotors, caps, plugs, wires, fuel filter and so on. I did the same stuff and i even adjusted the idle and the lowest it would go is 1000. I was trying a bunch of things and all of a sudden, when i unplug my EFI harness, the idles drops normal and i can adjust the screw to get 700 rpms. The only problem is when i plug the efi harness back, it shoots back up to 1500. I dunno if its my IACV or not but adjust the screw does make a difference. That leads me to think its fine. It's been idling high after the 5 speed swap and I have searched and no one else that has done the swap had high idle for the ka. I checked all the hoses for vacuum leaks, and I've checked the timing as well. I'm pretty much out of ideas. Ctune has looked at it as well and they are stumped! So any other suggestions would be helpful. Edit- O yeah, I already pulled codes and it shows 55, meaning everything runs fine.

04-01-2005, 08:22 AM	#2
the head Nissanaholic! Join Date: Jul 2002 Location: in a dark room mastering the art of typing with one hand Posts: 2,164 Trader Rating: (3) Feedback Score: 3 reviews	sounds like your IACV is stuck open claen that bich out with some carb cleaner probably just carboned up and stuck __________________ I never knew you could do that with an eggplant

04-01-2005, 09:01 AM	#3
Phlip Yes, I look like that Join Date: Mar 2002 Location: In my supervillain's lair Posts: 27,980 Trader Rating: (19) Rides Gallery: Phlip Feedback Score: 19 reviews	Are you still using the auto ECU? If so that is your problem, get used to it or get a manual ECU http://www.zilvia.net/f/showthread.php?t=74615 __________________ Weirdo And I write too!

04-01-2005, 10:17 AM	#4
drift freaq R.I.P. Aya, always love Join Date: Nov 2001 Location: Los Feliz/Hollywood Posts: 18,564 Trader Rating: (215) Rides Gallery: drift freaq Feedback Score: 215 reviews	normal auto ecu stuff, but if you go to the 5 speed ecu you will lose a few cool things. The auto ecu on a S13 is actually a secret weapon performance upgrade. Ya you get the funny drop to idle issue but the trade off is no speed cut!! Higher rev limit 7200 and a better curve . Yes a better curve!! Why because auto trannys are much different than clutch manual setups . So the ecu maps have a different curve to them. All the auto cars I have swapped have always been quicker useing the auto ecu. vs a 5 speed ecu car. __________________ "Having a lot of tracks on a song is like putting stickers on a car to get more horsepower" New Video https://www.youtube.com/watch?v=uebV1OnbRsw Buy my mounts! http://zilvia.net/f/sale-items/51531...ns-mounts.html http://zilvia.net/f/tech-talk/317539...e-mouts-6.html

04-01-2005, 09:42 PM	#5
Phlip Yes, I look like that Join Date: Mar 2002 Location: In my supervillain's lair Posts: 27,980 Trader Rating: (19) Rides Gallery: Phlip Feedback Score: 19 reviews	Damn, makes me angry that my auto ECU was for a single cam and my engine is a twincam __________________ Weirdo And I write too!

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