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: Dec 2007
Location: Northern Ca
Posts: 530
3 liter CIS engine fumbles, stumbles at start up and...

... I can keep it running with more gas. It feels like 2 cylinders are not playing with the rest.

This has happened about 3 times recently - and the "remedy" so far has been to get the rpm up to about 5500 (on the road under load) and then the rest of the engine comes back to life.

Directionally - does this sound like electrical, fuel or some other related?

Old 04-10-2015, 08:44 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #1 (permalink)
Registered
 
Walt Fricke's Avatar
 
Join Date: May 2004
Location: Boulder, Colorado
Posts: 7,275
So what year engine? 3.0s ran from 1975 or 6 (Euros) through 1983. Various changes along the way.

Pull some spark plugs - are they black (too rich on start-up maybe) or white (too lean running).

Sounds like CIS related.
Old 04-10-2015, 09:15 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #2 (permalink)
Registered
 
Join Date: Dec 2007
Location: Northern Ca
Posts: 530
Hi Walt,

It's a '76 Euro 3.0 with '78 sized CIS and 'slightly' enlarged throttle body. Also - it really oscillates on cold start up between 500-1700ish for about 45 seconds... WUR related I suppose.

I'll check the plugs tomorrow - thanks,
Old 04-10-2015, 10:09 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #3 (permalink)
ROW '78 911 Targa
 
timmy2's Avatar
 
Join Date: Jul 2011
Location: Salem, OR
Posts: 10,214
Garage
Vacuum leaks will cause the oscillation as well.

Old 04-10-2015, 10:27 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #4 (permalink)
Reply


 


All times are GMT -8. The time now is 11:19 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.