1998 Random cylinder misfires and code P0420 - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat
GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat

Go Back   GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat > Pontiac Bonneville > 1992-1999

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.

LinkBack Thread Tools Search this Thread
Old 10-07-2008, 11:41 AM   #1
Junior Member
Join Date: Oct 2008
Posts: 1
Thanks: 0
Thanked 0 Times in 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????
jllracer55 is offline   Reply With Quote

Similar Threads
Thread Thread Starter Forum Replies Last Post
Buick Century Misfires Cylinder 1 code p0301 susiespontiac Buick 3 03-17-2015 10:24 PM
Random Misfires SLE2005 2000-2005 6 03-05-2013 12:03 PM
Random misfires with code P0321 FaceShot 1992-1999 9 09-21-2009 08:23 AM
code p0420? BLKssei02 Performance, Brainstorming & Tuning 9 11-07-2008 06:26 PM
Help Please!! 03 SE pulled out code P-0300B random misfires. GM-Maine 2000-2005 8 03-18-2007 10:59 AM

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -4. The time now is 06:17 PM.