Check Engine Light
#1
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Ok, so I went out to the track last night...yeah, my times were bad, so I'm not going to tell you until I get better at launching her off the line
...But after I ran her one time, my "service engine soon" light comes on...
So, since she's new and I'm really paranoid about her right now (still got the new car buzz thing going), I decided to stop running her, and take her home. Before I left, though, I talked to a couple of other guys who were out there with Cobras. One of them was saying that every single time he first raced his, the check engine light would come on for either a sensor, or for the measurement of the fuel pressure inside of the tank, or other b.s. like that...and that you have to go into the computer itself, see what kind of code it's kicking out, and find out what needs to be fixed, or if the code just needs to be deleted from the computer. And then the light will go out, and it's not a big deal, it's just the car saying "Ummm, I'm not so sure if there's really something wrong, but I think you should know..." Most of the people I talked to were saying that I should've just gone ahead and kept running her, but what if the light actually means something, you know?
So I decided to drive her home. She seems to be driving fine, and I'm not hearing any wierd noises, or getting anything that seems out of order, and her fluid levels are all good, looked around in the engine bay, and that seems all good, so...
Well, I'm going to go ahead and put her on a diagnostic today when I get off of work, and hopefully it's nothing, and the light is gone by the time I wash her tonight...
So I'll let you guys know if she's OK.
Now, for where I was going with this. I'm not going to be going out to the track with her all of the time, but I will probably be playing with her quite a bit. If the check engine light just comes on like this because of the computer chip, and it's just something that needs to be reset of deleted, then I'm wondering now if it might actually be worth my money to invest in a little check-up equipment of my own, like a Predator (one of the guys I talked to last night had one of these, but he said it was $500, omg!). So has anyone else had any experiences like this with their own '03 or '04 Cobra, and should I be worried about it? And is it worth it to throw the money out there?
Thanks, guys, please let me know... <3
![04](https://themustangsource.com/forums/images/smilies/04.gif)
So, since she's new and I'm really paranoid about her right now (still got the new car buzz thing going), I decided to stop running her, and take her home. Before I left, though, I talked to a couple of other guys who were out there with Cobras. One of them was saying that every single time he first raced his, the check engine light would come on for either a sensor, or for the measurement of the fuel pressure inside of the tank, or other b.s. like that...and that you have to go into the computer itself, see what kind of code it's kicking out, and find out what needs to be fixed, or if the code just needs to be deleted from the computer. And then the light will go out, and it's not a big deal, it's just the car saying "Ummm, I'm not so sure if there's really something wrong, but I think you should know..." Most of the people I talked to were saying that I should've just gone ahead and kept running her, but what if the light actually means something, you know?
![Frown](https://themustangsource.com/forums/images/smilies/frown.gif)
![Dunno](https://themustangsource.com/forums/images/smilies/dunno.gif)
Well, I'm going to go ahead and put her on a diagnostic today when I get off of work, and hopefully it's nothing, and the light is gone by the time I wash her tonight...
![Smile](https://themustangsource.com/forums/images/smilies/smile.gif)
Now, for where I was going with this. I'm not going to be going out to the track with her all of the time, but I will probably be playing with her quite a bit. If the check engine light just comes on like this because of the computer chip, and it's just something that needs to be reset of deleted, then I'm wondering now if it might actually be worth my money to invest in a little check-up equipment of my own, like a Predator (one of the guys I talked to last night had one of these, but he said it was $500, omg!). So has anyone else had any experiences like this with their own '03 or '04 Cobra, and should I be worried about it? And is it worth it to throw the money out there?
Thanks, guys, please let me know... <3
#2
Needs to be more Astony
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sorry this reply isn't about the check engine light but..
Why don't you post the time slip numbers and maybe people can give you pointers on how to improve, no one cares of you ran a slow time with the Cobra, not everyone is a professional driver.
Why don't you post the time slip numbers and maybe people can give you pointers on how to improve, no one cares of you ran a slow time with the Cobra, not everyone is a professional driver.
#3
Stubborn Bear
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Take it by an autozone or maybe some oil change places that have a service shop. Most of the time they have readers they can hook up and tell you the code that tripped the CEL. Also should be able to tell you what that code means.
#4
Shelby GT500 Member
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make sure everytime you get gas, that you put the gas cap on tight. if you launch hard enough and the cap isnt completely on. it will come loose and cause the light to come on. but to be sure take it by advance auto. they will check it for free. if its the gas cap, it will go out after a couple on/off cycles
oh, and post the numbers. some of us have run crappy numbers. the only way to get better is w/ experience
oh, and post the numbers. some of us have run crappy numbers. the only way to get better is w/ experience
#5
Ok, so I found out that I was smart to be paranoid about her and leave the track, just to update you guys...
I went to AutoZone, and they put one of their little diagnostic code-finders on it, and it came up with two faults consistently, saying that cylinder #6 was misfiring. So it came down to the spark plugs or the coils...Nate (y2kcobrar) and I took a look at the spark plug for #6, and, what do you know, the ceramic piece on the inside of it had come loose and was contacting, so it wasn't firing at all...you could hear it when she was idling, or running at low RPMs, kind of a lub-lub-lub sound as she skipped over that cylinder...it was horrible! But we went back to Autozone, I bought a new set of spark plugs, we put those in, and what do ya know? She's running great again, and the check engine light went out the next day.
So, hmmm, maybe I should listen to my first instinct when stuff happens, I sure am glad that I didn't run her again! And, once again, I owe Nate big time for being my own little personal Mustang encyclopedia... :worship: :worship: :worship:
And, so since you guys almost made me feel less ashamed of myself, I'll tell you my time on the one run that I got in...It was 14.5, because I got an almost 2-second late start....
Which makes me like the slowest Cobra in history!!! No, she was great, once I got my start...if I just work on my launch, I think I should be able to get 12s or (hopefully, crossing fingers) low 11s out of her. I know by the way she feels that she can do it...maybe she just needs a better driver...
No, I know it will all come in time...I'll let you guys know more times next time I get a chance to run her, all right? In the meantime, anyone got any tips on launching at the start of the quarter mile? I've heard a lot of people saying start her in second gear, power shift, get the tires hot before you launch...I'm just looking for some tips from experianced mustang drivers, if you guys could provide them...I'd greatly appreciate it! Thanks...
But the Cobra is in good shape again, so I'm happy!!
So happy driving everyone! :drive:
I went to AutoZone, and they put one of their little diagnostic code-finders on it, and it came up with two faults consistently, saying that cylinder #6 was misfiring. So it came down to the spark plugs or the coils...Nate (y2kcobrar) and I took a look at the spark plug for #6, and, what do you know, the ceramic piece on the inside of it had come loose and was contacting, so it wasn't firing at all...you could hear it when she was idling, or running at low RPMs, kind of a lub-lub-lub sound as she skipped over that cylinder...it was horrible! But we went back to Autozone, I bought a new set of spark plugs, we put those in, and what do ya know? She's running great again, and the check engine light went out the next day.
![Banana](https://themustangsource.com/forums/images/smilies/banana.gif)
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![Banana](https://themustangsource.com/forums/images/smilies/banana.gif)
So, hmmm, maybe I should listen to my first instinct when stuff happens, I sure am glad that I didn't run her again! And, once again, I owe Nate big time for being my own little personal Mustang encyclopedia... :worship: :worship: :worship:
And, so since you guys almost made me feel less ashamed of myself, I'll tell you my time on the one run that I got in...It was 14.5, because I got an almost 2-second late start....
![Fuss](https://themustangsource.com/forums/images/smilies/fuss.gif)
![04](https://themustangsource.com/forums/images/smilies/04.gif)
But the Cobra is in good shape again, so I'm happy!!
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#6
Good to hear that you got new plugs and that fixed the problem! As for launching the best advice that I can give you is start moving on the last amber light and don't dump the clutch! In a high power IRS equipped car dumping it will probably cause lots of wheel hop and slow you down. Just ease into the gas in the beginning and increase the throttle when you know you have traction. Worry more about having fun and being safe than getting the best possible time- my .02 cents.
#7
the best i ever ran in my cobra was a 12.8. If you can hit a very low 13 or a high 12, your're doing great. As for low 11's, your have to invest a bit of money in mods to get there.
#9
i did a 11.89 on street tires and only an 2.93upper pulley, a cat back and open filter.these cars can run low 12s stock i've seen it. with the pulley and exhaust SCT tune i've spent a little over $1500. the thing you have to worry about is wheel hop if you get to much you can either break the half shafts or destroy the cover on the differential, assuming the half shafts are stock and ther is no IRS brace. as far as the launching goes if you are running street tires there really is no need to do a long burnout and i usually go around the water box and do just a small 2nd gear burnout to clean any crap off the tires. if your using Drag radials go around the water box and back into it and do a long smokey 2nd gear burnout. if you have the IRS brace i would launch the car around 3000rpm and nail the car down the track. if not i would slip the clutch and feel for spin, i usually floor it in the middle of 1st. again get out of it if you feel any wheel hop at all. hope this helps some and i'm glad you got your check engine light figured out. what kind of plugs are you using and what gap are they at?
#10
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Lindsay, congrats on the lack of a problem in your baby. If you decide to invest in mods, easiest thing to do to get a very good bit of "vroom" out of her is a new pully setup. In cobra, pullys help more than in regular mustangs. For the GT, steeda's been everyone's #1 pick, don't know about cobras though...
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