Ok I seen some posts via the "search" but they are from last year or later so I assume i would'nt get a response. I bought this car (01 A4 1.8T Q w/65k) a month ago.

I have noticed for the last 2-3 weeks that when I start the car for the first time of the day the rpm's bounce about 200-300rpms then drops to idle when warm. My timing kit should be here any day now, but will this stop the bounce? Also something I got a lil worried about I seen a coil in the glove box. So I asked the seller what it was, and he did'nt even no what it was.[sm=rolleyes.gif]

 

a picture of the coil would be nice?? if the rev counter jumps does the revs go up and down at the same time??? if not is could be a poor connection to the VSS sensor (vehicle speed sensor)

 

Sorry if the pic comes out bad this is used and does have Audi's symbol on it. One more Q's are all the stock fuel pumps fairly loud?

[IMG]local://upfiles/17719/8CEEC5C7A2A049D19DD6B5B8C7B36D24.jpg[/IMG]

 

you'll hear the fuel pump for the first 10-20 seconds, that's normal. as far as the bouncing RPMs, if it only happens when the car is cold its nothing to worry about, just warming up. if it happens when it's warmed up, it's likely a bad idle control valve

 

I don't think that part is off your car. I don't know what the heck that even is... it is not a coil like ignition coil if that is what you meant. Atleast not for your car. I think, (I have an A6 so I can't be sure for an A4) you have electronic ignition (no coil). You could tell by following the spark plug wires to the other end (not the spark plug) and it should connect to a flat plate.

Yeah the bouncing RPMs are not bad if the idle is not rough. You could replace/ regap your spark plugs for reduced bounce though. Usually a bounce indicates differing gaps on your spark plugs (unless your idle is rough).

 

I pulled the engine cover off and I got 4 of these connecting to the spark plugs. I just assume they are ignition coils. Still have no clue why someone would leave a used one in the glove box. I am not familiar with this type either so I dont know how to test it to see if its bad. Good thing is I put 800 miles on the car and have'nt had a light come up.

 

There was a recall on the ignition coils so maybe it was replaced and that was an old one. I know that my cylinder 1 and 4 ignition coils as of now vibrate out so im going to see if replacing it will help. It's not throwing codes but it's clearly not supposed to happen.

 

The bounce would have nothing to do with a VSS. Yes that is a coil. Ford refers to it as coil on plug. You can test it with a digital malti-meter by checking ohms and continuity of the coil primary and secondary. The only thing is you need to find specs for it somewhere. I had a problem on cold start up too. It would kinda studder at about 200-400 rpms and then go to idle. I took it to the dealer under warrenty and the made the computer relearn the throttle. it was good after that

 

Wow, that is a cracked out coil... yet another reason to go with the A6

 

One other thing that is weird, once in a great while my stock car alarm just goes off. I cant find a link to why it happens other than its allways at my house. Are there sensors on the windows? Like if a bug flies in the alarm goes off. Could these two problems be related?