Can low octane gas cause check engine light?
Thread Starter
Melting Slicks
Joined: Jul 2003
Posts: 2,529
Likes: 0
From: Gonzales LA
Can low octane gas cause check engine light?
Yesterday I had to get gas. Seems to be near impossible to find around here right now. I went to 6 gas stations before finding one that even had gas left but they only had 87 octane. I always use at least 91 octane but it was either that or run out of gas. This evening my check engine light came on. Could running 87 octane cause this or is it just coincidence? All of my temps and gauges seem to be within normal operating parameters and I can't hear anything that sounds different. I'm getting it scanned in the morning to find out what the code is but between it being the weekend, a holiday, and a major natural disaster the dealer MAY be opened Tuesday at earliest. 
Team Owner
Joined: Dec 2003
Posts: 57,408
Likes: 164
From: queensbury ny
light
if the car is RUNNING WELL,even though the ck.engine light is on,then you should be fine till tuesday.Bad gas can make your light come on.seen it many times.try a bottle or two of dry gas,ck your gas cap,and see if it goes out on it's own after that,in a day or two.it needs to cycle out.
Le Mans Master
Joined: Sep 2002
Posts: 5,187
Likes: 6
From: Oakville Ontario,Canada
Originally Posted by Ubenripped
Yesterday I had to get gas. Seems to be near impossible to find around here right now. I went to 6 gas stations before finding one that even had gas left but they only had 87 octane. I always use at least 91 octane but it was either that or run out of gas. This evening my check engine light came on. Could running 87 octane cause this or is it just coincidence? All of my temps and gauges seem to be within normal operating parameters and I can't hear anything that sounds different. I'm getting it scanned in the morning to find out what the code is but between it being the weekend, a holiday, and a major natural disaster the dealer MAY be opened Tuesday at earliest.
I remember testing it out....I put regular in my car and within an hour the check engine light came on... ran the gas out and put premium back in...was fine
Race Director
Joined: Aug 2002
Posts: 10,256
Likes: 96
From: not far enough from Chicago
Low octane in a high compression engine will cause gas to ignite under the compression (much like a diesel that has no spark plugs.) It's supposed to ignite when the spark plug fires, so you may end up with pinging or knocking. That is not good, and I would get some 93 octane in there as soon as possible. Hopefully you don't have too much of the low octane to be diluted by the high.
Team Owner
Joined: Sep 1999
Posts: 34,062
Likes: 4
From: Evans, GA
I have refuled several corvettes at Wally World (Murphy Oil Company) and never a problem. Also refuel the Cadillacs at the same place.
Check the gas cap and make sure it is tight, then clear the codes and see if the error code reappears before getting excited. I ran my 04 C5 on a couple of tanks of regular, when premium was not available, and never had a problem. The onboard engine control computer is smarter than we are.Of course, i don't drag or do WOT very often.
Good luck with the fix.
Check the gas cap and make sure it is tight, then clear the codes and see if the error code reappears before getting excited. I ran my 04 C5 on a couple of tanks of regular, when premium was not available, and never had a problem. The onboard engine control computer is smarter than we are.Of course, i don't drag or do WOT very often.
Good luck with the fix.
Le Mans Master
Joined: Feb 2002
Posts: 5,407
Likes: 1
From: HONOLULU HAWAII
Originally Posted by Ubenripped
Yesterday I had to get gas. Seems to be near impossible to find around here right now. I went to 6 gas stations before finding one that even had gas left but they only had 87 octane. I always use at least 91 octane but it was either that or run out of gas. This evening my check engine light came on. Could running 87 octane cause this or is it just coincidence? All of my temps and gauges seem to be within normal operating parameters and I can't hear anything that sounds different. I'm getting it scanned in the morning to find out what the code is but between it being the weekend, a holiday, and a major natural disaster the dealer MAY be opened Tuesday at earliest.
http://www.stengel.net/diccodes.htm
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Drifting
Joined: May 2005
Posts: 1,566
Likes: 52
From: Colorado Springs CO
I've used 87 before and never got a check engine light, but it's not impossible. I agree you should check the code though, to make sure it isn't something more serious. As far as the ping/knocking, your vette has a knock sensor in it to stop that, hence the reason you have lessened engine performance using lower octane fuel. As someone partially described, the ONLY difference between low and high octane is the FLASHPOINT of the fuel, meaning the higher octane has a higher flashpoint. The ping/knock is just a result of premature combustion due to a low flashpoint, which again, the knock sensor compensates for.
Bottom line: check the codes, if it's the fuel, use the octane boost and it will be fine temporarily. The sky IS NOT falling....
Bottom line: check the codes, if it's the fuel, use the octane boost and it will be fine temporarily. The sky IS NOT falling....
Thread Starter
Melting Slicks
Joined: Jul 2003
Posts: 2,529
Likes: 0
From: Gonzales LA
I knew about the traction control codes because I already had it scheduled to go into the shop next week for that. Didn't know about the rest though. All of these occured recently.
This car has a randomly possessed electrical system. The motor runs great and doesn't eat oil but I have had all types of minor electrical gremlins in the past. PCM and BCM was replaced under warranty about a year ago for randomly losing communication with everything. Had the windshield wipers randomly decide to turn themselves on or off and the wiper controllers were replaced. Every now and then I notice the internal lights such as dash lights and radio lights change intensity but the dealer never seems to be able to reproduce a lot of the errors.
Anyway, here are the codes:
PCM
------
P1415 AIR System Bank 1
TCS
------
C1243 BPMV Pump Motor Stalled
LDCM
------
B2264 Vertical Position Sensor Fault
U1064 Loss of Communications with BCM
RDCM
-------
B2283 Battery #1 Fault
B2285 Battery #2 Fault
U1064 Loss of Communications with BCM
U1096 Loss of Communications with IPC
U1255 Serial Data Line Malfunction
Oh, and I cleared the codes last night and the check engine light was gone this morning. Still have the TCS problems though. I have to rescan in a little while and see if any of the others came back.
This car has a randomly possessed electrical system. The motor runs great and doesn't eat oil but I have had all types of minor electrical gremlins in the past. PCM and BCM was replaced under warranty about a year ago for randomly losing communication with everything. Had the windshield wipers randomly decide to turn themselves on or off and the wiper controllers were replaced. Every now and then I notice the internal lights such as dash lights and radio lights change intensity but the dealer never seems to be able to reproduce a lot of the errors.
Anyway, here are the codes:
PCM
------
P1415 AIR System Bank 1
TCS
------
C1243 BPMV Pump Motor Stalled
LDCM
------
B2264 Vertical Position Sensor Fault
U1064 Loss of Communications with BCM
RDCM
-------
B2283 Battery #1 Fault
B2285 Battery #2 Fault
U1064 Loss of Communications with BCM
U1096 Loss of Communications with IPC
U1255 Serial Data Line Malfunction
Oh, and I cleared the codes last night and the check engine light was gone this morning. Still have the TCS problems though. I have to rescan in a little while and see if any of the others came back.
Racer
Joined: Oct 2003
Posts: 424
Likes: 2
From: Galena, OH
Originally Posted by 1Patriot
I have refuled several corvettes at Wally World (Murphy Oil Company) and never a problem. Also refuel the Cadillacs at the same place.
Check the gas cap and make sure it is tight, then clear the codes and see if the error code reappears before getting excited. I ran my 04 C5 on a couple of tanks of regular, when premium was not available, and never had a problem. The onboard engine control computer is smarter than we are.Of course, i don't drag or do WOT very often.
Good luck with the fix.
Check the gas cap and make sure it is tight, then clear the codes and see if the error code reappears before getting excited. I ran my 04 C5 on a couple of tanks of regular, when premium was not available, and never had a problem. The onboard engine control computer is smarter than we are.Of course, i don't drag or do WOT very often.
Good luck with the fix.
Gas Cap not tight is number one cause for this if you recently filled up. 
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
NONE of those would be fuel related!!!!! After you clear the codes, monitor the DTC for any receint codes and post them. My guess is that the code was sporatic and should clear.
The TCS code is another animal and need further troublechooting. What year car and what mods??
BC
The TCS code is another animal and need further troublechooting. What year car and what mods??
BC
Thread Starter
Melting Slicks
Joined: Jul 2003
Posts: 2,529
Likes: 0
From: Gonzales LA
Originally Posted by Bill Curlee
NONE of those would be fuel related!!!!! After you clear the codes, monitor the DTC for any receint codes and post them. My guess is that the code was sporatic and should clear.
The TCS code is another animal and need further troublechooting. What year car and what mods??
BC
The TCS code is another animal and need further troublechooting. What year car and what mods??
BC
The only code that came back is C1243 BPMV Pump Motor Stalled.
It disables my TC and ABS and says "Service Traction Control" and "Service ABS". It does it as soon as you start the vehicle.
