 Idle starts jumping around, After 1 or 2 minutes of running |
|
|
|
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. |
|
|
| championgt1 |
 May 28 2010, 10:59 PM
Post
#1
|
|
Don't embarrass me Filmore!  Group: Members Posts: 2,680 Joined: 3-January 07 From: Tacoma, Washington Member No.: 7,420 Region Association: Pacific Northwest  |
Car is a 74 djet. When I first start it cold it idles steady at around 1200rpm. After a minute or two it starts to jump back and forth from around 500rpm to 1200rpm or so. Any suggestions on what to look for? CHT? AAR?
|
   |
 
|
  |
Replies
| detoxcowboy |
May 29 2010, 06:44 PM
Post
#2
|
|
Senior Member Group: Members Posts: 1,294 Joined: 30-January 08 Member No.: 8,642 Region Association: Africa |
QUOTE(championgt1 @ May 28 2010, 09:59 PM)  Car is a 74 djet. When I first start it cold it idles steady at around 1200rpm. After a minute or two it starts to jump back and forth from around 500rpm to 1200rpm or so. Any suggestions on what to look for? CHT? AAR? i would check the AAR and its adjacent hoses, if its a cht issue it may really be an ecu issue and or as well.. the wierdness of it and that it happens in only 1 or 2 minutes (IMG:style_emoticons/default/confused24.gif) usually ARR leak makes high idle, PVC valve issue?? sounds like it is going lean on the mixturte after 2 minutes ect.. below is copied from the ecu doc. link: http://members.rennlist.com/pbanders/idle.htm My idle is rough and surges when it's warming up Lean idle mixture during warm-up. According Brad Mayeur, a 914 expert, who worked on these cars in the '70's at a Porsche dealership, poor running during warm-up due to lean mixture was a common problem on the 2.0L engines, not as common on the 1.7L's. The factory "fix" for this problem was to install a spacer between the CHT and the head. The spacer delayed the CHT's response to the changes in head temp, causing the ECU to deliver a richer mixture. I had this problem, and first made my own spacer, then got a very nice replica spacer from Brad, which totally fixed my warm-up issues. Locate Brad using Google if you're interested in getting a spacer. |
|
|
|
Posts in this topic
championgt1 Idle starts jumping around May 28 2010, 10:59 PM
dangrouche i got the same problem; it believe its a vacuum le... May 28 2010, 11:26 PM Bleyseng This is the way the idle gets warm, it jumps aroun... May 29 2010, 05:15 PM
Bleyseng first of all you must set the idle mix when the en... May 30 2010, 07:30 AM |
2 User(s) are reading this topic (2 Guests and 0 Anonymous Users)
0 Members:
|
Lo-Fi Version | Time is now: 1st June 2024 - 12:36 PM |
Invision Power Board
v9.1.4 © 2024 IPS, Inc.