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
 
}{arlequin's Avatar
 
Join Date: Jun 2003
Location: DC/Boston
Posts: 5,500
Garage
New plugs and wires, engine keeps POPping

1973.5T

Had a spark jump from the lead into the distributor cap causing a misfire and a stuttering car at part throttle. Changed the plugs and wires today. The spark is gone, but the car is making intermittent popping sounds at idle. You can even feel the exhaust pulse get stronger with each pop. To make things worse, the car feels like it's running on half power.

I replaced one cable at a time to avoid confusion of what goes where. Then again, the Hynes manual does not have a diagram showing exactly which tip on the cap goes to which cylinder, so I can't even double check my work. The cap itself is not labeled either.

I have two more things to go over, maybe a new cap and rotor, and then those infamous points... but I'm not entirely sure what to do to them... Does anyone have any ideas of what may be some possible causes of the pops or what to look for?

Thanks,
Dave.

Old 08-15-2003, 09:42 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #1 (permalink)
Registered
 
Join Date: May 2000
Location: Los Alamos, NM, USA
Posts: 6,044
Check the timing and point dwell (point gap). Adjust as required.
Old 08-15-2003, 10:08 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #2 (permalink)
Registered
 
Join Date: Mar 2001
Posts: 1,031
double and triple check your firing order....

Let us know what happens!
Old 08-15-2003, 10:35 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #3 (permalink)
Registered
 
marcesq's Avatar
 
Join Date: Aug 2001
Location: Sarasota, FL
Posts: 1,948
Garage
Popping can (not always) be a result of a leak in the exhaust system some where between the exhaust port and muffler tip. You should be able to hear the leak.
__________________
'94 CMC Firebird Trans Am
'86 951 LS1 (C-2) Gone
'77 911 3.2 (C-1) Gone but not forgotten.
http://www.pelicanparts.com/MotorCity/marcesq1
http://www.youtube.com/user/958Fan#p/u
Old 08-16-2003, 02:27 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #4 (permalink)
Moderator
 
304065's Avatar
 
Join Date: Dec 2001
Posts: 9,569
Re-check the connections at each wire-- sometimes they don't seat in the boots.

Your problem really sounds like a bad ground to the motor. Are your ground straps in good shape? I added a second one from the motor mount to the port chain cover, worked great. Ron has grounded everything to everything else. . . it's that marine experience
__________________
'66 911 #304065 Irischgruen
‘96 993 Carrera 2 Polarsilber
'81 R65
Ex-'71 911 PCA C-Stock Club Racer #806 (Sold 5/15/13)
Ex-'88 Carrera (Sold 3/29/02)
Ex-'91 Carrera 2 Cabriolet (Sold 8/20/04)
Ex-'89 944 Turbo S (Sold 8/21/20)
Old 08-16-2003, 05:53 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #5 (permalink)
Registered
 
Join Date: Dec 1999
Location: Novato, CA
Posts: 4,740
Pull your dist cap off and you'll see a small line cut into the rim of the distributor. That tells you where #1 wire goes. Proceed clockwise with the firing order.

Cheers,

Joe
Old 08-16-2003, 07:46 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #6 (permalink)
 
Registered
 
}{arlequin's Avatar
 
Join Date: Jun 2003
Location: DC/Boston
Posts: 5,500
Garage
Joe,

Thanks. That is exactly the info I've been looking for. Not sure why, but I was having a real tough time finding a diagram that numerically labelled all the nipples on the cap. Thanks to you I have a reference point.
__________________
dave
1973,5: one two thweeee!
no.don't.stop.
Old 08-16-2003, 02:15 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #7 (permalink)
Registered
 
}{arlequin's Avatar
 
Join Date: Jun 2003
Location: DC/Boston
Posts: 5,500
Garage
Ahhh... sweet sound of smooth idle. Thanks to all with your patience to deal with same old issues. Turns out after all that even though I changed the wires and plugs one at a time (to avoid a mishap) I managed to swap #3 wire with #5 wire on the cap.

All is well now, but does anyone know whether a conservative (limp mode) 30 mile drive with swapped wires could cause any problems?

Thanks again.
__________________
dave
1973,5: one two thweeee!
no.don't.stop.
Old 08-16-2003, 04:37 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #8 (permalink)
Registered
 
Zeke's Avatar
 
Join Date: Jan 2002
Location: Long Beach CA, the sewer by the sea.
Posts: 37,720
Nah, you're probably OK. Doesn't do any good, of course, but you're not the first.
Old 08-16-2003, 05:15 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #9 (permalink)
Registered
 
Join Date: May 2001
Location: Peoples Republic of Long Beach, NY
Posts: 21,140
30 miles is no big deal
__________________
Ronin LB
'77 911s 2.7
PMO E 8.5
SSI Monty
MSD JPI
w x6
Old 08-16-2003, 05:22 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #10 (permalink)
Registered
 
Join Date: Dec 1999
Location: Novato, CA
Posts: 4,740
Dave, you won't believe how many times I swapped wires while trying to be so careful, that's why I know.

I always end sleeping on it, thinking about it the next day, then going back to basics taking it one step at a time, that is, after getting over my frustration and feeling like an idiot. Amazing how quickly it all gets resolved with a little rest and a clear head.

Cheers,

Joe
Old 08-19-2003, 01:44 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #11 (permalink)
Registered
 
}{arlequin's Avatar
 
Join Date: Jun 2003
Location: DC/Boston
Posts: 5,500
Garage
Joe,

That's exactly how I felt. An hour's job turned into more like two or three and lasted into the evening. By that time the mosquitos were having their way with me. Consequently I ended driving home and double checking the line up the next day. Guess you learn a bit more each day.

__________________
dave
1973,5: one two thweeee!
no.don't.stop.
Old 08-19-2003, 03:53 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #12 (permalink)
 
Reply


 


All times are GMT -8. The time now is 03:28 PM.


 
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.