Pelican Parts
Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   Pelican Parts Forums > Porsche Forums > Porsche 911 Technical Forum


Reply
 
LinkBack Thread Tools Rate Thread
Author
Thread Post New Thread    Reply
Registered
 
Join Date: Jul 2004
Location: MD
Posts: 68
Porsche Crest Ping at 2200RPM -- Idle Mixture?

Hi guys,

Just lately my 89 Targa has started pinging at about 2200 RPM under light load, but only when at about 210F or above (needle at about 8:30). [list=1][*]I may just have a tank of bad gas. It seemed to start after a fill-up. I drained some out and put in some Octane +104 and topped up with 93 octane, but some ping remains, maybe less[*]A new wrench told me he adjusted the mixture last fall while doing a 45k service. I'm wondering if he leaned it out too much, and whether the idle mixture affects operation much at 2200 RPM? (The car never gets to 210F during the winter.)[/list=1]
The car has a Wong chip, but the chip has been in two years and this is the first pinging, so something is different.

Should I just run the tank almost dry and see what all fresh gas does, or is it worth cranking the mixture screw in 1/2 turn to see what happens?

Thanks,
RA

__________________
1989 Carrera Targa
1986 944 Turbo (totaled by trash truck)
Old 04-30-2006, 07:24 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #1 (permalink)
Registered
 
buster73's Avatar
 
Join Date: Feb 2004
Location: Wine country, Germany
Posts: 596
Garage
Beside bad gas it could be mixture, ignition timing or deposits in the combustion chamber. I would start with trying new gas (easy ) then checking the ignition timing and the mixture. Of course you should make sure the pinging you hear is indeed pinging/knocking and not something else.
__________________
Regards,
Guenter

73.5 911T, mod
Old 04-30-2006, 04:27 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #2 (permalink)
Registered
 
ruf-porsche's Avatar
 
Join Date: Feb 2000
Location: no where
Posts: 4,390
Garage
At over $3.50 a gasllon for premium here it better not be bad gas.
Old 04-30-2006, 05:16 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #3 (permalink)
Registered
 
Join Date: Dec 1999
Location: Novato, CA
Posts: 4,740
Is it possible that the SW chip runs so rich that your cylinders are now loaded with so much carbon that might be causing the pre-ignition?

Joe
Old 04-30-2006, 07:02 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #4 (permalink)
Make Bruins Great Again
 
Por_sha911's Avatar
 
Join Date: Dec 2003
Location: TN
Posts: 20,934
Garage
Quote:
Originally posted by stlrj
Is it possible that the SW chip runs so rich that your cylinders are now loaded with so much carbon that might be causing the pre-ignition?
That's easy to find out. If you are that rich, it would show on your plugs.
I would 1) check the plugs for fouling, 2) get a full tank of fresh gas then 3) try the stock chip. If nothing turns up, look at timing, and other items suggested.
__________________
--------------------------------------
Joe
See Porsche run. Run, Porsche, Run: `87 911 Carrera
Old 04-30-2006, 07:06 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #5 (permalink)
Registered
 
ischmitz's Avatar
 
Join Date: May 2002
Location: Santa Barbara, CA
Posts: 4,811
Garage
Send a message via Skype™ to ischmitz
Maybe your plugs are getting old. That can be enough to cause pinging. When is the last time you had them changed?

__________________
1974 Targa 3.6, 2001 C4 (sold), 2019 GT3RS, 2000 ML430

I repair/rebuild Bosch CDI Boxes and Porsche Motronic DMEs
Porsche "Hammer" or Porsche PST2, PIWIS III - I can help!!
How about a NoBadDays DualChip for 964 or '95 993
Old 04-30-2006, 07:13 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #6 (permalink)
 
Reply


 


All times are GMT -8. The time now is 09:27 AM.


 
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2025 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page
 

DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.