hey ,
started my car up let it warm up, then pulled out of my driveway to have no power and my check engine light flashing at me. It doesn't seem like all cylinders are firing and it sounds funny. there is also a strong aroma of rotten egg apparent. I was thinking its the coil pack but i had that replaces maybe 3 months ago along with plugs and wires. Car has 88k miles. Any ideas?

 

Flashing CEL on my A4 was bad Coil Pack. No power and funny engine sound is the same thing I had as well.

I would check your packs again and make sure one didn't go bad again, of course you don't wanna be driving that car around until you get it fixed.

 

rotten egg smell is your cat(s) burning.

 

coil pack could go bad in 3 months? Does that have anything to do with the smell in the cats? I drove the car last night and it was fine

 

What year/engine etc is your car? And yes parts can die fast. You also could be dealing with fouled plugs. Or it could be a different cylinder altogether.

 

Egg smell is cat like CCA4 said.

When my coil pack went bad it was only in Cylinder #2 and it was while I was driving home. I drove to work that day and it was just fine, went to lunch and it was fine, left work for the day and boom misfire with flashing CEL. If you move the Coil Packs around you could possibly track down what one is bad.

The smell could be coming from trying to drive the car still and it's not firing correctly, before driving it you definitely need to figure out what is bad or your could do serious damage to your motor.

 

apparently i have a one year warranty on the coil pack so my car is being towed to a garage and hopefully that is all that is wrong. Thanks for the help

 

To the more knowledgeable people that have posted in this thread, when I first read 'egg smell' my first thought went to a bad battery; as the unmistakable stench of leaking sulfuric acid from the battery is that of rotten eggs, and by process of logic, a bad battery could be resulting in not enough current hitting the plugs to ignite the fuel and thus cause the misfires. I then read that apparently a fouling cat can make the smell as well, and what you've said makes sense, but I just wanted to check if I may or may not have a reasonable track of thinking going on here?

 

A4Crag,
Your thought could make sense except for he listed "check engine light flashing", usually that is misfire caused by plugs or coil pack gone bad.

 

True, but I thought the codes flashed just for the fact that the misfire was detected, regardless of the actual cause, cuz the way I'm seeing it, if the coil pack isn't getting enough current from the battery, it wouldn't be able to ignite the spark, causing the misfire, and if it were the battery's fault, that code would still flash that it was misfiring no different than if the battery were fine and it really is a bad coil.

But that's where my uncertainty is and why I'm asking about it; I don't know for sure that the power delivered by the coil is taken from the battery. I've never gotten a solid answer as to if the battery simply provides the means for cranking and after that the ignition is run purely from the alternator, or if ignition is run from the battery after cranking and the alternator simply keeps the battery charged. If the ignition is driven by the alternator after cranking, then my idea is debunked; a bad battery would have nothing to do with a misfire generated by there not being enough power to create a spark since the spark would be relying solely on the alternator, and if that is the case, then yes, I would put my money on it being the coil's fault, but up until now, I've been under the impression that the coils are powered from the battery and thus a bad battery could be causing insufficient power to create a spark, causing a misfire, causing a flashing cel. Am I making any sense at all? lol