Check engine light - Page 3 - GM Forum - Buick, Cadillac, Olds, GMC & Pontiac chat

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.

Thread Tools Search this Thread
Old 02-05-2007, 04:55 PM   #21  
Senior Member
True Car Nut
Join Date: Mar 2004
Location: Ames, Iowa
Posts: 3,066
Thanks: 0
Thanked 1 Time in 1 Post
bill buttermore is on a distinguished road

Originally Posted by jv2351
looks to be a choice for a 96.

You mentioned scan tools. What are they? Are they worth the cost? Sounds like a tool that scans all systems and diagnoses problems
Scan tools give much more information than trouble codes. In addition to retrieving and clearing codes, they let you watch sensor outputs and computer values in real time. For example, you can monitor transmission temperature, coolant temperature, throttle position, and oxygen sensor voltage, among others. My Actron 9110 tool (not for OBDII) allows me to look at about 50 parameters. Many here have Actron 9145 scan tools. These cost about $200 - 300. The GM dealer'* scan tool, the Tech II, communicates with the PCM and allows you to run tests on components and systems. Nice but who can afford $2000+?
bill buttermore is offline   Reply With Quote
Old 03-16-2007, 02:01 PM   #22  
Senior Member
Posts like a Supercharger
Join Date: Apr 2006
Location: Schaumburg, IL
Posts: 185
Thanks: 0
Thanked 0 Times in 0 Posts
99SSEI is on a distinguished road

Something similar happened to me. I was using 93 octane gas, until recently, when the price shot up again. I filled the tank w/ 87 octane @ $2.47 / gall. One late night / early morning, I was racing a buddy'* Prelude on the highway. As the tranny shifted from 2nd to 3rd (approx. 90 mph), I noticed a jerk in acceleration. Then, the check engine light blinked several times then remained on. I noticed a rough idle and a loss of power from the midrange up. The next day, I had AutoZone (local parts store) read the code for free. I forgot the actual code, but it was "Multiple Misfires." We cleared the code and check engine light hasn't come back yet.

It had been almost 2 years since last plug / wire change over. I bought iridum plugs, ordered 8.5 mm MSD and MSD coils (center terminals are rusting). I pulled the closest plug to the coil and discovered that the side electrode had either melted or broken off, thus probably the cause of the mis-fires. Also, when pulling the wire, the terminal on the wire stuck to the plug. I had to buy a $5.00 replacement wire. I only replaced the front three plugs, for fear of tearing another wire out with the terminal missing (and not having the new wires handy). The rough idling is gone, however, the replacement wire doesn't exactly fit properly on the OEM coil. This is causing poor firing and I cannot give more than 50% throttle without what sounds like "bucking."

My new wires and coils have arrived today and I will be installing them tonight!!
Hopefully, this will bring my Bonnie back to normal levels.
99SSEI is offline   Reply With Quote
Old 03-16-2007, 03:19 PM   #23  
Junior Member
Posts like a Ricer Type-R
Join Date: Aug 2002
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
willwren is on a distinguished road

Now you see why you are required to run 91 octane minimum. If you're lucky, your pistons and valves survived.

Never run below 91 octane in an L67. Run 92 or 93 if you can get it after you change to a smaller pulley.
willwren is offline   Reply With Quote
Old 03-16-2007, 07:58 PM   #24  
Senior Member
Posts like a Supercharger
Join Date: Apr 2004
Location: Endwell, NY
Posts: 190
Thanks: 0
Thanked 0 Times in 0 Posts
sellncars is on a distinguished road

Originally Posted by jv2351
Fault codes are P0135 and P1406.

Replaced front oxygen sensor, egr valve/gasket, reprogrammed pcm calibrations.

Engine light still comes on occasionally....
P1406 has to do with your EGR Valve Pintle Position according to my Alldata.
sellncars is offline   Reply With Quote

Related Topics
Thread Thread Starter Forum Replies Last Post
1998 Catera - Check Engine Light, ABS Light and TC light on lucille2 Cadillac 2 02-10-2011 10:58 AM
Phantom Check Engine Light/Rough Engine/Coolant Temp. Gauge Whacky RWW2003 1992-1999 10 11-13-2009 07:00 AM
Check Gages-BRAKE light, trac off light, and Antilock light all on MissRockstar04 2000-2005 9 07-07-2009 04:12 PM
Engine miss, check engine light on - NO code mdrose64 1992-1999 12 07-16-2007 11:43 AM
Check engine light and traction off light on - hissing sound erics95se 1992-1999 11 04-08-2006 12:40 PM

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 Off
Pingbacks are Off
Refbacks are Off

All times are GMT -4. The time now is 12:29 PM.

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to and affiliated sites.