 Idle hunting, Where do I start? |
|
|
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
|
| steuspeed |
 Mar 16 2021, 07:24 PM
Post
#1
|
|
Senior Member  Group: Members Posts: 1,011 Joined: 12-July 11 From: Portland, Oregon Member No.: 13,308 Region Association: Pacific Northwest  |
I'm working on fixing my idle search. All new vacuum lines, plugs and wires. Car starts and runs smooth for about 1-2minutes, then the idle dumps and starts hunting up and down. My ECU knob was turned full clockwise by the PO. I turned it back to the factory setting.
Stock 2.0L 1973 car with Pertronix. Where should I look next? |
   |
 
|
  |
Replies
| saigon71 |
Mar 19 2021, 05:33 AM
Post
#2
|
|
Advanced Member Group: Members Posts: 2,019 Joined: 1-June 09 From: Dillsburg, PA Member No.: 10,428 Region Association: MidAtlantic Region 
|
Agreed that you are running lean at idle.
Start by turning the idle mixture knob on your ECU clockwise all the way - this is full rich. If this smooths out your idle, turn the knob counterclockwise a click at a time until the engine idle starts to hunt, then back off one click. Give the engine a little time to adjust between each adjustment. If that doesn't work: The 1973 model year used a ballast resistor of 270 ohms from the factory - it seems you are missing this. Pick up a resistor of this value and wire it in series with the CHT temp sender. This resistor effectively richens the mixture accross all operating conditions. Keep us posted on what you find. Good luck! |
|
|
|
Posts in this topic
steuspeed Idle hunting Mar 16 2021, 07:24 PM
Bleyseng Do you have the resistor installed? Mar 16 2021, 11:36 PM
steuspeed I see a white wire/connector/black wire to cylinde... Mar 17 2021, 04:59 PM rjames Are you sure no vacuum leaks?
Does changing the po... Mar 17 2021, 01:14 AM steuspeed
Are you sure no vacuum leaks?
Does changing the p... Mar 17 2021, 05:17 PM wonkipop not sure i can help as have a 1.8 L jet.
but have ... Mar 17 2021, 01:24 AM BeatNavy I think you're running lean. You need to trou... Mar 17 2021, 05:50 PM steuspeed
I think you're running lean. You need to tro... Mar 18 2021, 03:36 PM 914werke :agree: hunting idle is usually a symptom of lean ... Mar 17 2021, 06:09 PM steuspeed
:agree: hunting idle is usually a symptom of lean... Mar 18 2021, 12:09 AM mgphoto Most times it’s the idle screw on the throttle b... Mar 17 2021, 09:44 PM steuspeed
Most times it’s the idle screw on the throttle ... Mar 18 2021, 12:10 AM cary Concur with Rob & Rich, too lean. Mar 17 2021, 11:01 PM BeatNavy I wouldn't worry too much about the idle bypas... Mar 18 2021, 05:18 AM steuspeed
I wouldn't worry too much about the idle bypa... Mar 18 2021, 03:38 PM JamesM
Agreed that you are running lean at idle.
Star... Mar 19 2021, 08:45 AM rjames
Agreed that you are running lean at idle.
Sta... Mar 19 2021, 11:39 AM 914_7T3 My ‘73 had the same symptoms and it was indeed t... Mar 19 2021, 01:28 PM |
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:
|
Lo-Fi Version | Time is now: 7th November 2025 - 09:58 AM |
Invision Power Board
v9.1.4 © 2025 IPS, Inc.