1992-1999 Series I L27 (1992-1994 SE,SLE, SSE) & Series II L36 (1995-1999 SE, SSE, SLE) and common problems for the Series I and II L67 (all supercharged models 92-99) Including Olds 88's, Olds LSS's and Buick Lesabres Please use General Chat for non-mechanical issues, and Performance and Brainstorming for improvements.

New plugs, bad MPG

Thread Tools
 
Search this Thread
 
Old 04-04-2012, 02:59 PM
  #1  
Senior Member
Posts like a Supercharger
Thread Starter
 
ggenovez's Avatar
 
Join Date: May 2009
Posts: 161
Received 4 Likes on 4 Posts
ggenovez is on a distinguished road
Default New plugs, bad MPG

Hi all,

I replaced my plugs a couple of weeks ago, I was getting around 25 MPG, and the new ones are giving me 18.

I don't race so what'* up? They're Delco copper plugs... gapped to .060

Thanks

1992, bonny SE
Old 04-04-2012, 03:07 PM
  #2  
Senior Member
True Car Nut
 
2kg4u's Avatar
 
Join Date: Sep 2006
Location: Windsor, Ontario / Detroit, Michigan
Posts: 4,816
Received 241 Likes on 198 Posts
2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of
Default

Did you properly seat all the wires? Is there a chance a wire was damaged when you pulled it off? Is your car hesitating on acceleration? Is the CEL lit? Is it flashing?

Inspect the area to see if you disconnected or broke anything when you changed the plugs. Look for any disconnected or damage vacuum lines.
Old 04-04-2012, 03:26 PM
  #3  
Senior Member
Posts like a Supercharger
Thread Starter
 
ggenovez's Avatar
 
Join Date: May 2009
Posts: 161
Received 4 Likes on 4 Posts
ggenovez is on a distinguished road
Default

Yes, everything was seated correctly. I'll pull the wires and run a resistance test through them. No CEL light or flashing.

I'll check the vac lines as well.

Thanks!
Old 04-04-2012, 05:19 PM
  #4  
Retired Senior Admin

Expert Gearhead
 
Danthurs's Avatar
 
Join Date: May 2006
Location: Sheboygan Wisconsin
Posts: 29,661
Likes: 0
Received 28 Likes on 24 Posts
Danthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to allDanthurs is a name known to all
Default

Pull the plugs again and inspect them. If any look different or odd, take a picture and post it up here. You may have a bad plug.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
SilverSleeper8704
Buick
15
03-30-2020 09:41 PM
jessieboi1984
1992-1999
18
09-15-2005 02:51 PM
mkaake
1992-1999
23
05-05-2005 02:25 AM
BonnieBrougham
Lounge
3
12-16-2004 05:38 PM
L27Buick
1992-1999
6
05-06-2004 05:16 PM



Quick Reply: New plugs, bad MPG



All times are GMT -4. The time now is 08:26 AM.