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Check Engine Light

57K views 17 replies 11 participants last post by  Slybacon-34 
#1 ·
Well, I got a CEL yesterday. But the car is running fine! No hesitation, no rough idle, nothing noticeable at all. Checked the fuel cap and door and everything looked fine as well.

I tried to get the codes read at AutoZone, but the reader kept throwing a "Connection Error." He said he'd gotten the same error twice earlier in the day when connected to another vehicle, but was able to connect on the third try. No luck with my 6 on three tries so I just took it home. HE thought the scanner could be having problems, but could he have been using the wrong scan tool? He checked the tool for the model year, but I have no idea what a "CAN bus-capable scan tool" is and didn't think to ask him when he was trying to read.

Anyway, I'm still in warranty and bringing it to the dealer tomorrow, but I was wondering if I should drive it (about 13 miles) or trailer it to them. Also, if I do drive it, what's the max speed I should go?

Any recommendations are appreciated (especially from crossbow! :) )
 
#3 ·
So long as the CEL isn't flashing, you should be safe to drive it to the dealer. The manual recommends getting the car towed only if the CEL is flashing.
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No flash - solid as a rock.

Thanks! I'll be heading there first thing in the morning.

And next time I'll RTFM.

:D
 
#4 ·
They were probably using their real basic OBDII scanner at autozone. Our cars do require the CAN compatible scanner which is a newer protocol that only some of the more expensive OBD II scanners support. I have the Autoxray 5000 which is CAN compatible and works nicely on the 6. It gives quite a bit of data for a DIY scanner.
 
#5 ·
Well, I got a CEL yesterday. But the car is running fine! No hesitation, no rough idle, nothing noticeable at all. Checked the fuel cap and door and everything looked fine as well.
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I wouldn't be surprised if it WAS the gas cap. Had a CEL a few months ago, same symptoms as you, and checked and re-checked the gas cap. Dealer got a "loose gas cap" code, and reset the light, figuring the problem was solved. Light comes back on four days later, and the dealer then decides to run a pressure check on the gas tank, and discovered that the gas cap itself was faulty. They replaced it, apologizing three times for not finding the problem the first time.

Good luck, and let us know what the dealer finds out...
 
#6 ·
If you have no trouble code reader, as a sanity check you can disconnect the battery cable, negative cable (is highly recommended) and see if this will reset the error codes. If the code reappears and chances are it will then find some one who can get the error code.

I use the AutoEnginuity software package.
 
#8 ·
If you disconnect the battery the code and the FFD will be lost.

Maybe Crossbow will be of some assistance. :D
[/b]
Not going to reset anything. I'll leave it all up to the dealer. They've been really good so far, and I don't expect it to change.

Yesterday when I checked the gas cap all I did was make sure it was tight. Today I took it off and when I did there was a little "puff" like the tank had more pressure in it than I remember. Not a lot, just a little bit - less than opening a coke. But it was noticeable.

Anyway, when I find out for sure what code it threw and the solution I will post it all here.

Thanks for all the suggestions!

:)
 
#9 ·
Error code was P0442 - Small Evap Leak.

They performed an evap test several times and it passed each time.

They also installed a new PCM and TCM update for my vehicle and did their free multipoint inspection (brake pads, tire tread, fluids, etc.)

Total time was a little less than 100 minutes from the time I pulled into the service bay until I was back on the road - and for 10 of that they weren't officially open.

The only thing I can figure is the gas cap came loose or I didn't tighten it properly or something.

Happy camper.
:D
 
#12 ·
I just had this exact problem. I took my girl's 6i into the shop and they told me it was a small vac leak that was probably due to not tightening the gas cap enough....thanks for telling me something i already new and charging me 70 bucks for it! The problem is that after making sure that the gas cap was tight, the damn light has come on again....the first time it came on when she had a half tank of gas left, this time it's the same thing....do you think that I could have a faulty gas cap/tank? I need some help guys!!!
 
#18 ·
Hey guys, so I was getting the same code (sorry forget all the codes) for the small evap leak so I bought a new gas cap. Then the next code in the line, large evap leak came up which the dealer said needed a new evap canister for $400. That didn't work so then they said the evap solenoid (located behind the computer on the firewall) required replacing for another $500.

Long story short the issue was a wire short underneath the rear of the car. The wire was green (corroded) and I just had a mechanic cut it and use a heat wrap to splice it. Reset the code and all is good. I know this worked because like 8 months later I had the same issue on the wire right beside the one we repaired, could see the green corrosion.

Hope this helps, sorry no pictures.
 
#13 ·
I had a weird CEL issue last night. Went to start the car after coming back from work, and it the engine would crank but it wouldn't start?!?! I tried giving it a little gas (ehemmm...I know EFI), but that didn't work. Waited 20 seconds, then tried again....then it worked?! Let the car run for a minute or two, noticed that the CEL had come on...scratched my head and proceeded to drive on. CEL stayed on until I got home. Shut-off engine, checked oil and a few other things. Restarted car, CEL was still on?! Started car this morning.....guess what.....CEL is not on anymore LOL what the heck>!??! The car is running fine, no hesitation or rough idle. I did leave the car in my covered garage (but not heated) for a little over a week. The weather has not been particularily cold here (lowest temp was maybe -10 Deg Celsius). Car is due for an oil change, so it will be going to the dealership either this week or next week.....

Anyone ever seen this happen before?



I just had this exact problem. I took my girl's 6i into the shop and they told me it was a small vac leak that was probably due to not tightening the gas cap enough....thanks for telling me something i already new and charging me 70 bucks for it! The problem is that after making sure that the gas cap was tight, the damn light has come on again....the first time it came on when she had a half tank of gas left, this time it's the same thing....do you think that I could have a faulty gas cap/tank? I need some help guys!!!
[/b]
 
#14 ·
I just had this exact problem. I took my girl's 6i into the shop and they told me it was a small vac leak that was probably due to not tightening the gas cap enough....thanks for telling me something i already new and charging me 70 bucks for it! The problem is that after making sure that the gas cap was tight, the damn light has come on again....the first time it came on when she had a half tank of gas left, this time it's the same thing....do you think that I could have a faulty gas cap/tank? I need some help guys!!!
[/b]
Check the link crossbow posted. It has information on this problem. The test referenced is the one performed, so I'll just have to wait and see if it happens again. Luckily I'm not a high mileage driver and I have an extended warranty, so I have time.

:D
 
#15 ·
Well I had a CEL come on also. Not sure what to do, nothing seams wrong... My problem is I am in England with an American car, the dealer is no help. I have 3.0 which they do not have here. I will try to reset it and check the gas....leak but I know the cap is tight.

Had the same problem the MILITARY auto shop's code reader would not recognize my car. I will take it down town but the labor rate kills me + the exchange rate means I pay about twice as much as everyone else.

Has anyone seen other problems other than gas related? Thanks for any help. I will reply as to how it works out...
 
#16 ·
Well I had a CEL come on also. Not sure what to do, nothing seams wrong... My problem is I am in England with an American car, the dealer is no help. I have 3.0 which they do not have here. I will try to reset it and check the gas....leak but I know the cap is tight.

Had the same problem the MILITARY auto shop's code reader would not recognize my car. I will take it down town but the labor rate kills me + the exchange rate means I pay about twice as much as everyone else.

Has anyone seen other problems other than gas related? Thanks for any help. I will reply as to how it works out...
[/b]
See my last post about reading the link crossbow provided. Could be the same problem, but without the code reader you won't know for certain.
 
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