I have a bad miss-fire and hard braking problems in my car a few weeks back. Took it to the dealer here. They changed the spark plugs, turbo gasket and a hose for the brake vacuum system. When I got it they told me everything was ok. (no codes) When I got it, driving home it happened again (miss-fire+ hard braking).

Since the dealer here(phil) is new to audis they are not used to the common problems of the B5s. Since I have been researching here, I learned that it could probably be the coil packs. Do you guys think I should just change the coil packs. Will the hard braking problems go away too? They seem to always appear at the same time. Help....

 

You didnt mention a CEL... You got a CEL? You sure its a miss fire? Describe your hard braking problem more and provide a little more detail.

 

no cel at all.....the dealer even gave me the diagnosis log(no faults)... although I have had the abs and brake lights come on and off for a month now(abs module-i think). It sure seems like a mis-fire. its running really rough. With regards to the braking. I have to put my foot down really hard to make it come to a full stop... I mean really hard.(I had the pads checked and brake system checked -no problems) wierd.....

 

the best way to describe the hard braking.... It's the same when I had to drive a manual car when its in neutral and its being towed with a rope.... seems its all manual, no brake boost to help it stop...

 

If it was a missfire, youd definately have a flashing CEL. Have you checked your brake fluid? A bad ABS module wont affect braking power-only your ABS functionality. Either way i wouldnt drive it till you have it figured out.

 

yep it should have a stored soft error code, the miss fire and breaks could be linked because the engine is cutting out for a second by the sound of it or RPM dropping too low then picking up just another way to look at the issue

 

Change your fuel pressure regulator. Either your cylinders are flooded or are being starved of fuel. That's the cause of your misfire.

 

How can you be so sure? It could be several different things, and if he was actually having a fuel delivery problem, it would be accomponied by a CEL or soft code. He doesnt even have a CEL or code to even say with confidence that it is a miss fire. He is just tying to explain what it what it feels like. A flashing CEL goes with miss fireing hand in hand with these cars. So until you read up more and adapt to what the proper trouble shooting procedures and methods are for our cars, please dont act like you have the solution to a problem that doesnt even exist. If it were a fpr problem, that would create either a lean condition (which would cause detonation as opposed to a missfire and at least store a "lean" code) or a rich condition (which would cause "flooding"-as you say-and cause a missfire triggering the CEL.)

 

thanks for all your input....
what do you guys think if I just do all or at least one by one until it gets fixed.
"Rough Running At Idle - MAF, Ignition Coil, Spark Plug(Done), VAC Leak, O2 Sensor, TB, CTS"

I really hope to get it done soon. I found out that giac is available here(phil.)

Once this is solved, I have decided to get myself that and a dv for xmas

 

Go to autozone and check for codes again, even if the dealer says there is nothing stored there before you start replacing parts.

Hard braking isn't related to backfiring or spark plugs. could be brake vacuum assist, or vacuum leaks.