I started up my '01 A4 last night to move it further up the driveway and it started shaking really bad and the CEL started flashing. I revved the engine and it smoothed out to normal and the CEL stopped flashing. After checking around, this problem seems to be mainly attributed to an ignition coil(or coils) going bad. None of the posts I read mentioned the car stop shaking, which mine did. Also I read if there is a misfire the car will put itself in limp mode. Someone suggested it was because I hadn't driven the car all day and the temp went from around 77 down to 50 degrees.

So today I started the car up, didn't shake or anything, drove it around, got up to 45( Nowhere near a highway) and go the RPM's up past 3000 a few times to see if I was in limp mode. As far as I can tell I'm not.

Mainly asking, I had a misfire on ignition last night, car evened itself out, then today it ran fine. I'm taking it to get looked at Monday but is it even safe to drive it?

 

did you pull the codes? that would be number one on the to do list.

how many miles are on the spark plugs? how many miles on the MAF?

when a coil dies, its not normally intermittent. its usually permanently dead. a misfire doesnt necessarily put the car in limp mode, and its hard to tell if you are or not without a boost gauge or code reader.

see if you can make the car do it again. you dont want to drive anywhere with a flashing CEL, but its possible it was a random problem that went away on its own -however unlikely.

 

Haven't had time to do anything to the car. Happened last night and now I have to go to work. The CEL isn't flashing, it flashed last night when I first cranked it up, after I revved the engine it stopped. Can I hold out until Monday?

 

as long as the CEL isnt flashing you can probably get away with driving it. but if you are on the road and it starts doing it again, you have to pull over immediately or risk causing damage. dont drive the car unless you have to.

it could be the O2 sensors being sluggish. they do need a few seconds to warm up, if they are taking longer then normal it might cause a misfire right as you start the car. there would be a code stored.

 

I'm only driving to work, try to take someone else car tomorrow to work. Monday I'm going to call about having the ignition coils changed.

The RPM's aren't sitting high(idle right under 1000) no odd smells, no smoke, nothing feels out of the ordinary.

 

dont replace things without knowing they are wrong. an Audi will bankrupt you with that mentality. before anything else, get the codes scanned and post them here. also answer the questions from my first post.

 

Oh sorry, I bought the car used about 6 years ago with 40,000 on it. I just hit 100,000 the other day.

I drove to work fine, got up to 60 mph, went over 4 bridges, nothing seemed wrong. Got off work, car started fine and I just got home and it drove fine. I don't quite know what to make of it.

 

I had same thing with my car yet no one responded to my thread lol...

I've done plugs and coil packs, still having issues...plug wires next, who knows how long its been since theyve been changed

 

It would also help to know what engine you have, but like ghost said, you gotta diagnose the problem before you start replacing stuff.

I had a pretty good misfire a couple months ago, and it was the coil pack, but I pulled the codes, found out which cylinder, swapped it to a different cylinder, and verified the misfire followed.

A few weeks ago, I started having another mild misfire, pulled the codes and found out it was random misfires on 3 cylinders. The plugs had about 12K miles, so I replaced them, did the seafoam treatment, and an oil change, and the car runs better than ever.

Since your car seems to be driving alright for now, go to AutoZone or some other big box auto store and get your codes read for free, write them down, and post them. From there, (plus what engine you have) there are quite a few people here with almost unlimited knowledge on how to help you out...

 

Same goes for this too... get the codes, tell us the engine, and diagnose before you start replacing more stuff, unless of course, you have an unlimited repair budget...