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.

1998 Random cylinder misfires and code P0420

Thread Tools
 
Search this Thread
 
Old 10-07-2008, 11:41 AM
  #1  
Junior Member
Thread Starter
 
jllracer55's Avatar
 
Join Date: Oct 2008
Posts: 1
Likes: 0
Received 0 Likes on 0 Posts
jllracer55 is on a distinguished road
Default 1998 Random cylinder misfires and code P0420

Hello everyone, new here, but thought I would try to make a post and see if I can get some help with this because its really starting to annoy me that I cannot figure out what is wrong. Have a 1998 Pontiac Bonneville that the check engine light first started coming on. Got the code and it was P0300 and saying that cylinder 3 was misfiring. So from that, replaced all 3 coil packs with new coil packs, changed spark plugs and wires and it seemed to be running better. Ran ok for a while but then the code came back and the transmission wasn't wanting to shift properly. so I took a whole sunday to replace the Transmission filter and gasket. put a fuel filter on, oil filter and oil, and still was running really bad. Pulled off cylinder number 1'* spark plug wire and it broke, so we went and got new wires, put them on and it seems as if now it hesitates more and more than what it did before. now when you start it up at idle it first chugs really bad and then slowly the idle evens out like its not getting enough gas to hardly even start the car, let alone accelerate and go, any suggestions????
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
susiespontiac
Buick
5
12-23-2019 01:04 AM
SLE2005
2000-2005
6
03-05-2013 12:03 PM
FaceShot
1992-1999
9
09-21-2009 08:23 AM
BLKssei02
Performance, Brainstorming & Tuning
9
11-07-2008 06:26 PM
GM-Maine
2000-2005
8
03-18-2007 10:59 AM



Quick Reply: 1998 Random cylinder misfires and code P0420



All times are GMT -4. The time now is 01:45 PM.