Emission light came on for the first time

jcavz24x

Active LVC Member
Joined
Aug 9, 2004
Messages
72
Reaction score
0
Location
FL
About 10 minutes after filling up on 87 octane my emission light came on. I have been using 87 for a few months now and this is the first time it came on. At first it stayed lit and after an hour it started blinking(misfire).
My car is due for a tune up ('01 ls v6 75k)but i am wondering what i should know before bringing it to a shop?
Im sure it was bad gas on top of being 87. Is it likely to just need new plugs or should i expect other things such as coils?
...im aware i should stick with 93octane..lesson learned...

Chris
 
Valve cover gaskets is what it will probably need... As far as i know 87 will not kill your coils or plugs...
 
Is it safe to use the 1/4 tank of gas that is left and waiting to fill up with 93?
 
like i said... i really dont think the 87 had anything to do with the misfire problem... get the codes pulled from the car and post them... put whatever gas in you want... OH and DONT ERASE THE CODES
 
The difference in price between 87 and 93/91 for a full tank of gas is only $3.60. So just put 93/91 in it all the time. If you are going to count the whole year its about $187.20. Now if you take into account that your computer will retard the timing on your engine for the lower octane fuel you will lower you gas mileage. Now the savings on fuel is costing you more money to run. You will loose about 20% f your mileage to 87 octane. So for example, average MPG is 20. You use 87 octane and loose 20% = 4mpg less. The loss of 4 mpg = 72 miles per tank less. Well thats 4 gallons of gas at current prices = $7.12. How much more for 93/91 octane? $3.60 - $7.12 = $3.52 savings. Wow, I saved money by buying 93/91 octane, almost to hard to believe, but it is!
 
like i said... i really dont think the 87 had anything to do with the misfire problem...

of course the 87 had EVERYTHING to do with the misfire.

That what lower octane does!!!!! and that is why it is dangerous to use. Man you continue to amaze....

The V6 is not known to have the valve cover issue - that is Gen1 V8 and some early 03 V8
 
87 will not kill your plugs i'm sorry.. as long as he doesnt have his foot in the peddle all the time he would never notice a difference... With my custom tune i have ran 87 octane a hand full of times with no issues at all! the compression doesnt have everything to do with the OCTANE ethier smart guy... it also has to do with valve lift and lobe sep.. I could build a 12:1 compression motor and run 91 pump gas all day long.. BUT LET ME guess if it was your setup it would be 110 race gas rtight... al because of the 12.1!.. 87 will NOT KILL YOUR PLUGS!

maybe kill a cylinder if your at WOT all day everyday! but normal daily driving you would never see any kind of difference....thats the beauty of OBD2!!! Short term and long term fuel trim will make it work...
 
the compression doesnt have everything to do with the OCTANE ethier smart guy... it also has to do with valve lift and lobe sep..

dude - back away from the keyboard. Think about your statement. Not trying to pick on you - many of your posts are just not factual.

I did not say anything about plugs. We are talking mis-fire.

Octane rating is the ability of gasoline to resist detonation. The higher the rating the more you can squeeze it before it combusts on it own. So in a high compression engine - you have to use a higher octane rating to prevent the mixture from igniting before the spark does it.

To save you - read up -
rookie version - > http://science.howstuffworks.com/gasoline3.htm
The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites. When gas ignites by compression rather than because of the spark from the spark plug, it causes knocking in the engine. Knocking can damage an engine, so it is not something you want to have happening. Lower-octane gas (like "regular" 87-octane gasoline) can handle the least amount of compression before igniting.

The compression ratio of your engine determines the octane rating of the gas you must use in the car. One way to increase the horsepower of an engine of a given displacement is to increase its compression ratio. So a "high-performance engine" has a higher compression ratio and requires higher-octane fuel. The advantage of a high compression ratio is that it gives your engine a higher horsepower rating for a given engine weight -- that is what makes the engine "high performance." The disadvantage is that the gasoline for your engine costs more.

Here is a much deeper read on it - > http://www.lincolnvscadillac.com/showthread.php?t=48616
 
Last edited:
dude - back away from the keyboard. Think about your statement. Not trying to pick on you - many of your posts are just not factual.

I did not say anything about plugs. We are talking mis-fire.

Octane rating is the ability of gasoline to resist detonation. The higher the rating the more you can squeeze it before it combusts on it own. So in a high compression engine - you have to use a higher octane rating to prevent the mixture from igniting before the spark does it.

[/url]

I will not argue that point...

what I'm saying is that him driving his car normal and running 87 will not hurt anything... like i said in the first post, It wont hurt the plugs.. And it wont cause the misfire... if anything its just going to ping from to low of octane not misfire completely.... that was the point i was trying to make... I understand what you are saying.. but at the same time, if he can't afford 91 or just decides he doesn't want to.. his engine isn't going to explode because of the 87 octane.. its just like the car says 91+ so is my car going to have misfire problems because I can't run the 93... its such a small difference and low of power its not going to be that big of a deal
 
sorry - nope.

There are many, many thread exactly like this one - someone 'thinks' they are saving money (did you read Leo's post #5?) and it ends up hurting.

Just do a search - many CEL lights. If Ford could make the car run safely on lower octane - they would have - it would be a huge selling point, but that fact is that they could not. 91+ period.

I'm sure there are people that put in 87 and have not yet had an issue - but it's simply not responsible to tell people it's ok.

And again - the V6 is not know for the valve cover gasket issue - only Gen1 V8 and early 03 V8.

So his issue 'could' be simply a fluke of timing and having a coil go bad - but much more likely that the low octane gas is causing the car to mis-fire.
 
of course the 87 had EVERYTHING to do with the misfire.

Octane rating is the ability of gasoline to resist detonation. The higher the rating the more you can squeeze it before it combusts on it own. So in a high compression engine - you have to use a higher octane rating to prevent the mixture from igniting before the spark does it.
No trying to be an ass Quik, but you just kinda contradicted yourself.
87 would not cause a "misfire", it would cause detonation. Or even pre-ignition under the correct circumstances.

Given the time to adjust itself the LS' computer would eventually retard ignition timing and enrich the fuel/air ratio to the point where even using 87 octane you could still run WOT and not have any detonation.

But back to the original point, the misfire. He claims to have been running 87 octane for several months before with no problem. The V6 is not immune to the dreaded dead C.O.P. problem that the V8s have. The C.O.P.s have the same guts inside, even though they look a little different on the outside.
He could have very well pumped some bad gas, or there could be water in it, or it could even be that his plugs are fouled because they're too cold for 87. Hell it could be dirty fuel injectors have fouled the plugs, or for that matter it could be a dead injector that isn't spraying when its told to. You, of all people, should know not jump to conclusions when it comes to diagnosis. ;)

Or maybe the jokes on us... ? :shifty: :p
 
No trying to be an ass Quik, but you just kinda contradicted yourself.
87 would not cause a "misfire", it would cause detonation. Or even pre-ignition under the correct circumstances.

Given the time to adjust itself the LS' computer would eventually retard ignition timing and enrich the fuel/air ratio to the point where even using 87 octane you could still run WOT and not have any detonation.

well - the blinking CEL light symptom is generalized as a 'misfire' but really a knock - so you're right it's a pre-ignition - generalized as a 'misfire' - happy? ;)

The PCM does not seem to be able to adjust enough - there are many threads on 87 octane causing a CEL - which is a little baffling - you would think it would just retard the heck of it and run like crap - but there must be a lower limit to the amount of delta.
 
I ran the engine until the original tank was empty and put 93 in. It is still having problems..at this point im sure something needs replaced. Is the whole valve cover replacement issue mainly with the v8? not sure where to start
 
There's no car rule saying that your valve covers will never ever leak, so its always possible but very unlikely. The dealership I work for bought a car from auction one time with just over 12k miles on the ticker and only about 2 years old. Well, first person to test drive it comes back and complains about smoke rolling out from under the hood and the smell of oil. Valve cover gasket on the drivers side was leaking like a sieve.

But given what I can see, you probably want to start with having that code read, and proceed from there.
 
yes - the valve cover gasket issue is a Gen1 V8 issue.

you may have a bad coil - the V6 doesn't seem to have it as a common issue - but it is possible.

Have you reset the PCM? you do this by disconnecting the battery for 10min+

Auto-zone, Pepboys, ...most can read the code for free.
 
i am going to try the pcm reset...if i turn the heat on without AC there is a smokey smell with a hint of raw gas(not too bad)
 
light stayed off but the car still ran the same...might be giving the CTS a try
 
PCM reset you have to unplug the batter and press the brake several times. Don't ask me why this works but it does.. It discharges the electrical system.

and yes autozone is a savior! anywhere you can get an OBDII reader! Those things are an absolute blessing and should come with every Lincoln LS sold! :D

Also no CEL, doesn't nessesarily mean no codes. The codes you pull are going to point you in the right direction.
 
The first time (I was 17, give me a break) that I put 87 octane in my car, a coil blew. Coincidence? No. Don't do it. Don't argue about it. 91+ no questions or excuses.
 
The first time (I was 17, give me a break) that I put 87 octane in my car, a coil blew. Coincidence? No. Don't do it. Don't argue about it. 91+ no questions or excuses.

yes it was a coincidence... Cant you explain how Octane killed that COIL... I will BET NOT!
 
well - the blinking CEL light symptom is generalized as a 'misfire' but really a knock - so you're right it's a pre-ignition - generalized as a 'misfire' - happy? ;)

The PCM does not seem to be able to adjust enough - there are many threads on 87 octane causing a CEL - which is a little baffling - you would think it would just retard the heck of it and run like crap - but there must be a lower limit to the amount of delta.

well now that we are talking about this.. I dont see the fuel causing the coils to go bad.. Maybe if it was a fuel that burned alot SLOWER it could cause the coils to go bad for the fact that the amperage to the coils would have to increase to allow a strong enough spark to over come the plug gap and the cylinder compression and fuel resistances to burn... But i dont see that happening from a fuel that burns faster
 
Actually the V6 gen1 also has VCG issue too...

I had misfires around the same mileage OP has (maybe 5-10k more).. replaced VCG and coils.. problem solved

and i always use 91+
 

Members online

No members online now.
Back
Top