Parts Catalog Accessories Catalog Tech Info Tech Forums
  Search our site:    
 Cart  | Project List | Order Status | Help    

Go Back   PeachParts Mercedes ShopForum > Technical Information and Support > Tech Help

LinkBack Thread Tools Display Modes
Old 08-27-2001, 10:48 AM
Posts: n/a
Octane Question

I have an '86 560 SEL with 106K miles. I have owned the car for 6 years and have always used regular gas in it. I know MB says to use premium and I sometimes fill with that, but 95% of the time I use regular. The gas octane in my area is 87 regular, 89 for middle grade, and 91 for the premium blend. I would think that after 6 years if anything bad was going to happen it would have already. So why is it that MB says to use premium? The car gets in the 17-18 mpg on the highway and I never get any spark knock in city or highway driving.
Reply With Quote
Old 08-27-2001, 11:28 AM
G-Benz's Avatar
Razorback Soccer Dad
Join Date: Apr 2001
Location: Dallas/Fort-Worth
Posts: 5,711
If you suffer no ill effects, then stay the course.

It's just a theory, but there may be additives in the higher grades that help with keeping injectors clean, reducing carbon build-up, etc., etc. Then again, it could just be "snake oil". Higher octane fules have a hotter "flash point", which inhibits detonation in high-compression engines, or lower-compression supercharged and turbocharged engines.

As your car gets older, some problems that might crop up could be solved simply by upgrading the octane you currently use.
2009 ML350 (84K) - Family vehicle
2001 CLK430 Cabriolet (71K) - Wife's car
2005 BMW 645CI (124K) - My daily driver
2012 Mustang V6 (60K) - Daughter's car
Reply With Quote
Old 08-27-2001, 12:00 PM
Posts: n/a
The reason you get by with regular is that part of the ignition control system on you car is a knock sensor. If knock is sensed, the ignition is retarded to prevent it. Retarding the ignition timing, decreases power and increases fuel consumption. This is the subsystem that has saved your engine.

Good luck,
Reply With Quote


Thread Tools
Display Modes

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

Similar Threads
Thread Thread Starter Forum Replies Last Post
Fuel Requirement Question MBR Tech Help 2 07-31-2003 11:27 AM
Newbie Question josephcorderomd Diesel Discussion 1 07-07-2003 10:59 AM
Radiator & Oil Cooler Question cKoeller Tech Help 1 03-25-2003 05:50 PM
Radiator & Oil Cooler Question. cKoeller Vintage Mercedes 0 03-25-2003 01:30 PM
Octane rating -anti-knock or less carbon deposit? yamil78 Tech Help 2 03-12-2003 04:15 PM

All times are GMT -4. The time now is 07:55 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2011 Pelican Parts - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page