check engine light on and off

[leavenedbread]

Hi Guys,

My daughter has an '02 Beetle. The check engine light has been coming on and staying lit for a few days and then going off. We brought it to the dealer. They said it checked out fine. Maybe it was gasoline/gas cap related. Just run it and let them know if it happened again. A few days later it went on and off again and again up to now. She has used the same gasoline from the same station (87 octane) and has double checked the cap.

Before the check engine light problem, the airbag light was constantly on. The dealer replaced the cluster. Again, they said there was not actually anything wrong with the airbag system. Indeed the airbag light works properly now.

I'm wondering if we got a bad cluster to replace our bad cluster. I believe the replaced cluster was brand new because it had the protective film on it when they installed it. (whatever that is worth)

Finally, we have noticed that the check engine light seems to come on mostly when the weather is wet or raining. Other than telling the dealer this tidbit, is there anything else I should know or intelligent question(s) I should be asking them?

Thanks,

Leavenedbread

[SC2ner]

I doubt the issue is related to the cluster again. A bad cluster is not a common problem. Not unheard of but not common. The gas cap is not as common either. But more so then a cluster. If you really feel it's not sealing right then replace it.

If the check engine light comes on while its raining that could most likely mean that you need a new coil and spark plug wires. Plug wires go bad, coils get cracks in them. Moisture gets in and the light goes off. The reason it comes on when it's not raining could be from humidity. Even though you cannot feel the misfire does not mean that it's not misfiring. If you haven't replaced the spark plugs in a while you might want to do that as well.

[ricebike]

when it does go on, goto your nearest autozone/ advance auto parts for a free trouble code scan... let us know what that code is

don't go to the stealership since they charge for this free service at the parts stores i mentioned above...

[SC2ner]

Originally Posted by ricebike

when it does go on, goto your nearest autozone/ advance auto parts for a free trouble code scan... let us know what that code is

don't go to the stealership since they charge for this free service at the parts stores i mentioned above...

However unlike advanced auto where they only give you a code and you still have to diagnose it (which in some cases it could be something completely unrelated), the "stealership" will actually tell you what the problem is. So you may pay a couple bucks, but it saves you a ton of time. Maybe when you work for a dealership yourself, you will be educated to join in on a conversation. There are reasons why dealer parts are more and it's not because they are greedy.

Trust me, people who shop aftermarket have no clue. I buy some aftermarket parts myself, but only on certain things. Mostly because they are performance related. Important things I always go to the dealer. One it has a 1 year garunteed warranty, and two they are the right parts. Say you bought a ABS module for your car... did you happen to know that there are about 13 different ones for your car? Did you get the right one... I highly doubt it. The aftermarket places would carry one module and hope it works for all.

As I said, there are reasons; better quality, warranties (that you don't have to fight to get covered), exact part, proper part for vehicle identification number, proper spec... and so on. You are probably one of those who puts platinum plugs in your car because it sounds cool and you do not understand how a ignition system works. Let alone if its a waste spark system. But platinum and iridium sounds cool so you buy it.

Please don't make remarks of things you don't know or understand and I won't have to call you out and make you look like and idiot. Who am I? A certified expert vw parts specialist. yeah... I think I know these cars better then you.

[ricebike]

don't get your panties in a bunch, dude- no need to flame here

i'm suggesting one of the alternatives to going into a stealership

read the code, clear it... when it comes back on w/ the same code... then go get it to the stealership for proper diagnosis

sometimes a code springs up d/t the gas cap not tightened by the service station & in time it'll go off after a few on-off cycles... i've seen this many times

as for platinum plugs, most vehicles nowadays use platinum for extended maintenance interval, but they risk having the plug seize to the cylinder head after a couple of years so that's a double edge sword there... only ngk has an alloy-coating on the threads that help deter that problem (will using a dab of anti-seize on the threads a good thing in this case?--- oops going off topic)

as for aftermarket, there's brands out there that are comparable & sometimes better than oem, but in important parts like timing belt sets or key component sensors... i goto the manufacturer for them

[SC2ner]

Plugs seizing is not as common on newer cars. It is more known to happen on air cooled cars because the heads would get so hot. Putting anti-seize lubricant on the plug threads will not hurt anything. You should do this even though it is not as common on newer vehicles it is still possible. Most good techs practice this. It will not hurt anything. Don't get it on the electrode.