Im new to this website so I don't really know how to post stuff but I just bought a 2002 audi a4 1.8t Quattro and have some concerns
1. When I turn it on from the rpm goes up and down then stops. It's not much that it goes up and down but I'm wondering if that is bad?
2. Is when I turn the steering wheel it makes a hissing sound but sometimes it won't make a sound when I'm turning.. Need some help thanks.

 

1. Does your car shake when that happens ? You might have a random misfires.
2. Are you talking about the time when you turn the steering wheel all the way to the left or right ? If that's what you are talking it's power steering system. It's just there to tell you that it's working.

 

No it doesnt shake but you can hear that the engine revs up and down for a bit then after 3 seconds it stays at a normal rpm.

and for the steering wheel, its all the time if im making a right or left hand turn it makes a hissing sound and its only when im at slow speeds

 

are missfires bad?

 

You need to get Vag-com or go to your local autopart store and ask them to scan it... But if there isn't any CEL then I don't know if it's going to pick up.

About steering wheel, check the power steering fluid and see if you have any. If you don't you will have to go to the stealership and buy it there since local autopart stores don't carry power steering fluids.

 

Misfires will lead to more problems overtime.

 

x2 on power steering fluid. and for the rpm going up and back down it could be a small vac leak.

 

how do you replace the misfires?

 

My A4 does your 1) - sometimes (not always, and only cold) it revs up a bit (sometimes a lot) as soon as I turn it on. Then it goes down again. Sometimes also the RPM creeps up a bit (500 maybe) when I'm waiting at the lights near my house.

I was told this was a faulty oil temperature sensor, but I had this replaced and it still does it. Nothing else prohibitive shows up on a scan.

 

but re-Igniting them,? nah u need to replace your coils if you are misfiring.