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rpmdiag, Tech and Instructor
Category: Audi
Satisfied Customers: 8073
Experience:  Since 1975
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Hard engine miss with above average acceleration. 2012 a4.

Customer Question

Customer: Hard engine miss with above average acceleration. 2012 a4.
JA: Thanks. Can you give me any more details about your issue?
Customer: Normal acceleration, no problem and smooth. Hard acceleration above 2000 RPM and hard miss and/or stumbling. I instantly let off and accelerate moderately and smooth unless hard accelerate again. No codes and already changed spark plugs and coil packs 2 months ago from a #3 misfire. replaced all. also just tried unplugging the MAF sensor to see if it would run different. same or worse
JA: OK got it. Last thing — JustAnswer charges a fee (generally around $18) to post your type of question to Audi Experts (you only pay if satisfied). There are a couple customers ahead of you. Are you willing to wait a bit?
Customer: need to clean or replace air filter as well not done yet, but seems consistent and weird for that to be the issue]
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Customer: only if I can stop issue?
Submitted: 1 year ago.
Category: Audi
Customer: replied 1 year ago.
moderate acceleration feels smooth. above moderate to heavy acceleration misses and stumbles.
no codes
Replaced spark plugs and coil packs couple months ago after a #3 misfire code.
unlugged MAF sensor for half a mile to see if it changed. No changes or worse/similar
Need to clean or replace air filter (but I can't see this being the issue with this info) (only happens under heavier acceleration)
Expert:  rpmdiag replied 1 year ago.

Hi, I’m Ron and I can help you.
I have been in this business since 1975 and also teach automotive repair. I am confident
we can resolve your problem together. Please understand that I don't know your skill
level. I can't see, smell, hear, or touch the vehicle either, so it may take a few replies to
get to satisfactory results. Please be patient!
I also try to give all of the information you may need, expecting a “positive rating” in
return. I will also continue assisting you after you have rated me, if necessary. If there
is any reason I cannot get a positive rating, please let me know why “in advance”, so I
can go another direction for you. I am sorry you’re having this problem; I’ll help you
through it.

You need to check your injectors for a loss of ground or being dirty. There can also be an engine issue and you should check compression static and running.

Thanks, Ron

Customer: replied 1 year ago.
Ok thanks.....was just looking up the injectors a few minutes ago :) will see what i can find out with them from here :)
Expert:  rpmdiag replied 1 year ago.

Good, thanks again, and please don't forget to rate me and keep this link in case you still need me later on.


Customer: replied 1 year ago.
Will do and will do ;) ill let you know from here what's happening
Expert:  rpmdiag replied 1 year ago.

Thanks again,


Customer: replied 1 year ago.
Hello.....did some more research and thought i would let you know for future possible reference. ....i purchased (and called ahead to advanced auto) over the phone the replacement coil packs and plugs. Not paying too much mind to it i went ahead with the denso iridium plugs. In research i found many people having issues and using the ngk laser platinum more like oem was the difference for them. I stopped and got another set of plugs from napa and purchased the ngk laser platinum. Installed .....and so far no more miss during boost! Seems to be the difference right now!