 2056 D-jet, running poorly, CHT on #4 is waay off |
|
|
|
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. |
|
|
  |
| Bill Meyer |
 Mar 15 2012, 03:04 PM
Post
#1
|
|
Newbie  Group: Members Posts: 44 Joined: 11-October 07 From: Prairie Village, KS Member No.: 8,210  |
My fresh 2056 is really running poor during break in, low power, slight miss maybe. One of the issues I've noticed is when using a laser temp gauge (pointed at the exhaust manifold, directly off the head) I've found #4 is running around 230 Degrees while all other cylinders are in the 330-360 range. I suppose it's more of a EGT temperature as I'm measuring the header, not the head, but regardless number 4 is out of whack and probably where some of my trouble is.
Pulling the #4 plug and it is noticibly wet, sort of oily too. I've got good spark there, swapped plugs too, checked wires. Any ideas what to look for next? |
   |
 
|
| VaccaRabite |
Mar 15 2012, 05:25 PM
Post
#2
|
|
En Garde! Group: Admin Posts: 13,442 Joined: 15-December 03 From: Dallastown, PA Member No.: 1,435 Region Association: MidAtlantic Region |
#4 is not firing, or only firing intermittantly. You car probably feels like it has no power at all.
Carbs? If so, pull the idle jet and clean the circuit, then do the same for the mains. But it was always my idles that got crap in them. Clean the spark plug. Fouled plug won't spark. Check valves and the other stuff, but if it was a new build they should be fine. Zach |
|
|
|
| ChrisFoley |
Mar 15 2012, 06:21 PM
Post
#3
|
|
I am Tangerine Racing Group: Members Posts: 7,925 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None 
|
QUOTE(Vacca Rabite @ Mar 15 2012, 06:25 PM)  #4 is not firing, or only firing intermittantly. You car probably feels like it has no power at all. Carbs? If so, pull the idle jet and clean the circuit, then do the same for the mains. But it was always my idles that got crap in them. Clean the spark plug. Fouled plug won't spark. Check valves and the other stuff, but if it was a new build they should be fine. Zach (IMG:style_emoticons/default/slap.gif) OP says he has good spark. Title says D-jet. I can think of two things: Intake leak; bad injector |
|
|
|
| Bill Meyer |
Mar 15 2012, 08:27 PM
Post
#4
|
|
Newbie Group: Members Posts: 44 Joined: 11-October 07 From: Prairie Village, KS Member No.: 8,210 |
Thanks Chris, I do have an extra injector so I'll try that tomorrow. As for intake leak, do you mean on the runners with the large rubber connector? or is there another place they can leak?
QUOTE(Racer Chris @ Mar 15 2012, 07:21 PM) QUOTE(Vacca Rabite @ Mar 15 2012, 06:25 PM) #4 is not firing, or only firing intermittantly. You car probably feels like it has no power at all. Carbs? If so, pull the idle jet and clean the circuit, then do the same for the mains. But it was always my idles that got crap in them. Clean the spark plug. Fouled plug won't spark. Check valves and the other stuff, but if it was a new build they should be fine. Zach (IMG:style_emoticons/default/slap.gif) OP says he has good spark. Title says D-jet. I can think of two things: Intake leak; bad injector |
|
|
|
| aircooledtechguy |
Mar 15 2012, 09:05 PM
Post
#5
|
|
The Aircooledtech Guy Group: Members Posts: 1,966 Joined: 8-November 08 From: Anacortes, WA Member No.: 9,730 Region Association: Pacific Northwest |
To check for an intake leak, get the engine idling. Then use a can of carb cleaner with the thin tube attached to the spray head. Spray around EVERY joint, seal and gasket in the entire system from the throttle body to the head where the manifold attaches. If the RPMs momentarily rise as you spray, you have a leak there. If you find a leak, don't stop thinking it's the only one, continue until the whole system has been checked.
Common areas are the plenum to runner seals, small injector seals, cracked vacuum hoses, etc. |
|
|
|
| Prospectfarms |
Mar 17 2012, 09:23 PM
Post
#6
|
|
Member Group: Members Posts: 495 Joined: 7-March 11 From: Louisville, KY Member No.: 12,801 Region Association: Upper MidWest |
Last summer Cap'n K. posted a refinement to the "carb cleaner spray to find vac leak" procedure: check small areas at a time, get the straw very close, spray a little, and wait a few seconds before moving on. For years, I'd just fogged a portion of the engine hunting a leak. That sorta works, but this is much better.
|
|
|
|
| 76-914 |
Mar 17 2012, 09:48 PM
Post
#7
|
|
Repeat Offender & Resident Subaru Antagonist Group: Members Posts: 13,500 Joined: 23-January 09 From: Temecula, CA Member No.: 9,964 Region Association: Southern California
|
You don't have 3 & 4 inj leads crossed do you?
|
|
|
|
| Bill Meyer |
Mar 20 2012, 08:52 PM
Post
#8
|
|
Newbie Group: Members Posts: 44 Joined: 11-October 07 From: Prairie Village, KS Member No.: 8,210 |
Not sure, but wouldn't that cause both 3 and 4 to not fire at all?
QUOTE(76-914 @ Mar 17 2012, 10:48 PM) You don't have 3 & 4 inj leads crossed do you? (IMG:style_emoticons/default/birthday3.gif) |
|
|
|
| 76-914 |
Mar 20 2012, 09:07 PM
Post
#9
|
|
Repeat Offender & Resident Subaru Antagonist Group: Members Posts: 13,500 Joined: 23-January 09 From: Temecula, CA Member No.: 9,964 Region Association: Southern California
|
Nope, just makes it run like hell. Ask me how I know. (IMG:style_emoticons/default/mad.gif)
|
|
|
|
| brant |
Mar 20 2012, 09:12 PM
Post
#10
|
|
914 Wizard Group: Members Posts: 11,623 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains 
|
also the injector leads (broken wire on the plug in or harness)... or injector points can cause a dead cylinder.
|
|
|
|
|
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:
|
Lo-Fi Version | Time is now: 13th May 2024 - 02:02 PM |
Invision Power Board
v9.1.4 © 2024 IPS, Inc.