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
 
keithdog72's Avatar
 
Join Date: Feb 2004
Location: Canton, GA
Posts: 104
Send a message via AIM to keithdog72
Question Ignition Troubleshooting??????

I am having some trouble getting my 75 2.7 to run properly. I am getting fuel and the CDI box is fine. The engine will fire intermittently and then die. I am fearing a bad coil. I would like to know when I should be getting power to the coil and where? Should the +terminal be getting power with ignition on? what about the -side? I have rechecked the ground points and everything seems to check out. What am I missing? This has to be something simple, as the engine will fire sometimes. Please help, I am getting frustrated TIA
Keith

__________________
1975 911 Targa
1972 VW Beetle
2004 Mercury Mountaineer
2003 Suzuki Intruder 800
Old 04-14-2004, 09:41 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #1 (permalink)
Registered
 
Lorenfb's Avatar
 
Join Date: May 2003
Location: Manhattan Beach, CA
Posts: 2,350
With the CDI system, there's no power at the coil. You probably have a fuel related
problem. Check out this web site (www.systemsc.com) on the Diagnostics page
under "No Start".
__________________
Have Fun
Loren
Systems Consulting
Automotive Electronics

'88 911 3.2
'04 GSXR1000
'01 Ducati 996
'03 BMW BCR - Gone
Old 04-15-2004, 06:43 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #2 (permalink)
Registered
 
Join Date: Dec 1999
Location: Novato, CA
Posts: 4,740
Dirty points?
Old 04-15-2004, 02:21 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #3 (permalink)
Registered
 
keithdog72's Avatar
 
Join Date: Feb 2004
Location: Canton, GA
Posts: 104
Send a message via AIM to keithdog72
brand new set of points
__________________
1975 911 Targa
1972 VW Beetle
2004 Mercury Mountaineer
2003 Suzuki Intruder 800
Old 04-15-2004, 02:24 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #4 (permalink)
Registered
 
Early_S_Man's Avatar
 
Join Date: Dec 1999
Location: TX USA
Posts: 9,804
Send a message via Yahoo to Early_S_Man
Porsche Crest

Keith,

Same suggestions I have made a dozen times in the past month ... remove electrical panel, then CDI, clean grounds, 14-pin connector, 3-pin connector & braided gound cable-- crimp sides of individual Faston connectors, remove double-ground tab on CDI unit box ... wire brush & clean with Brakleen & then apply silicone grease when tab reinstalled, remove & clean power wires at 3-position fuse block, etc., etc. ... and apply silicone grease at CDI unit connections after proper operation is verified!!!

Do bench check of CDI system with new wiring in a test jig as suggested in this latest thread:

no start questions??
__________________
Warren Hall, Jr.

1973 911S Targa ... 'Annie'
1968 340S Barracuda ... 'Rolling Thunder'

Last edited by Early_S_Man; 04-19-2004 at 03:05 PM..
Old 04-15-2004, 02:47 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #5 (permalink)
Senior Member
 
Superman's Avatar
 
Join Date: Feb 2000
Location: Lacey, WA. USA
Posts: 25,305
Huh? Did you say something, Warren?
__________________
Man of Carbon Fiber (stronger than steel)

Mocha 1978 911SC. "Coco"
Old 04-15-2004, 03:03 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #6 (permalink)
 
Registered
 
Early_S_Man's Avatar
 
Join Date: Dec 1999
Location: TX USA
Posts: 9,804
Send a message via Yahoo to Early_S_Man
Porsche Crest

Supe,

... basically, I think I said the wiring and connectors in these cars are showing their age and need a bit of oxidation cleaned off ...

... BEFORE you start spending big $$$ to replace coils, install MSD, etc. ...

People ASSUME that wiring, coil, CDI needs to be replaced, AND, sure enough ... when they do that the car runs much better!!! Of course they have a pile of perfectly good parts, in most cases, lying on the garage floor, or in the trash ... that only needed to be cleaned, tested, re-connected with Dow Corning 4, 111, or 112 on all of the connectors ...

BUT, doing the dirty, slow, & tedious work doesn't have the 'glamour' of new wiring and a new MSD, now does it???

Naw ... forget what I said! It's more fun to spend lots of money and brag about how GREAT the car runs after the so-called 'upgrades' ...
__________________
Warren Hall, Jr.

1973 911S Targa ... 'Annie'
1968 340S Barracuda ... 'Rolling Thunder'

Last edited by Early_S_Man; 04-15-2004 at 03:23 PM..
Old 04-15-2004, 03:16 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #7 (permalink)
dtw dtw is offline
GAFB
 
Join Date: Dec 1999
Location: Raleigh, NC, USA
Posts: 7,842
Warren, sometimes I wanna switch professions, become a pharma salesman, and sell you some Prozac. I could make a killing. You are one fired-up dude, but I wouldn't change a thing. Rock on!
__________________
Several BMWs
Old 04-15-2004, 03:30 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #8 (permalink)
Registered
 
keithdog72's Avatar
 
Join Date: Feb 2004
Location: Canton, GA
Posts: 104
Send a message via AIM to keithdog72
Just cleaned everything really thouroughly. All the ground points and all the connectors. I am starting to think that this problem could be fuel pressure related as the car WILL fire and then it dies. I pulled an injector and got ALOT of pressure. So I guess I can rule out the Fuel Pump. Not really sure what happened to my baby. Any advice is helpful.
__________________
1975 911 Targa
1972 VW Beetle
2004 Mercury Mountaineer
2003 Suzuki Intruder 800
Old 04-15-2004, 04:33 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #9 (permalink)
Registered
 
Lorenfb's Avatar
 
Join Date: May 2003
Location: Manhattan Beach, CA
Posts: 2,350
Warren is right on. Don't waste money until you understand and solve the
problem. The problem is still undefined.

Try moving the sensor plate when starting the car to add more fuel or
spray some carb cleaner into the intake when it starts to die.
__________________
Have Fun
Loren
Systems Consulting
Automotive Electronics

'88 911 3.2
'04 GSXR1000
'01 Ducati 996
'03 BMW BCR - Gone
Old 04-15-2004, 08:17 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #10 (permalink)
Registered
 
keithdog72's Avatar
 
Join Date: Feb 2004
Location: Canton, GA
Posts: 104
Send a message via AIM to keithdog72
ok, dumb question which way should I move it to add more fuel?

__________________
1975 911 Targa
1972 VW Beetle
2004 Mercury Mountaineer
2003 Suzuki Intruder 800
Old 04-15-2004, 08:48 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #11 (permalink)
Reply


 


All times are GMT -8. The time now is 12:32 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.