ok so at low rpm any throttle from about 1400 to 2200 rpm it stumbles then its fine. its continual. i have been told to change the egr valve first and then the o2 sensors. could it be anything wrong with the opti or spark plugs. i am going to change all the fluids and plugs. anything else i can try would help. has anybody else had this issue and fixed it?

 

have u had it scanned for trouble codes?

 

yup no codes

 

yes, it could be the egr, it could also be the o2's, it could also be a spark plug, a vacuum leak, running way too rich, too lean, if it's an A4 it could be a flakey torque converter locking and unlocking. Do you get my drift? It could be a host of things so let's start with least expensive.

check ALL of your vacuum connections. If you have to, spray some starter fluid near them to see if it gets sucked in and the engine revs a wee bit. if not, then you have no leaks. As for EGR, do you require emissions where you live for the year car it is? If not, block it off. Does it get better?

Changing the plugs and wires is not a bad idea either and these wires are very reasonable and I've been running them for more than a year

http://www.jegs.com/i/JEGS/555/40225/10002/-1

you can get NGK TR55's for about $2 each at adv auto

does it run better now with new plugs and wires and checking for vacuum leaks?

If it still has issues, do you have an exahust leak before the O2's ?

If none of that works, it's time for data logging to see what is going on at that rpm range