HELP! a3 1.8t (agu) misfire

kev peacham

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This problem started after i was driving hard when the car was warm but now its doing it more or less all the time now. Its like a boost leak but its not because i have checked. Changed spark plugs a few times, new maf sensor, new ignition amp, new fuel filter, n75 bypass and its still there. Havent changed coilpacks because i have heard there reliable on the agu engines. Some one help please. Got told by a audi specialist near me it could be the flywheel??
 
I would do the throttle body next as its cheap to clean and then readapt it
 
If you have done all of that the next thing to check is the connections and loom for the coil packs. We had this problem with Prawns A3 a few years back, changed plugs, tried mafs and did loads of work looking for it. Turns out the coil loom was split from heat and wear and was shorting on the cam cover.

Have you vag-com'd it yet?
 
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I have had it on vag com at the audi specialist and nothing came up. I will have a look at coil loom as its in shop for this problem on thursday and if i can solve it it will save me a nice bit of ££££
 
You can buy loom replacement kits from Awesome GTI I think.
 
It is on full throttle when it happens. If i just build it up on the accelorater its ok
 
I would defo look at coil packs in one way or another; that's exactly what Prawns did when the loom split.

Try driving it from stone cold and see if it is fine then.
 
Change coilpacks or check loom do you mean

Check the loom for any splits or cracked wires, if there are any then undo the insulsting tape to expose the wires and insulate any cracks and then retape the entire loom. Check the earths too.
 
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Ill check that tonight and write back later with the outcome. Thanks
 
My money is on coil packs, autho still check your wiring.

If you have got the standard coil packs, ditch them for tfsi ones. I had a night mare with the standard packs failing and creating the exact same issue as you are getting. Awesome sell the tfsi coils and adaptor plates, and they are cheapest as well.
There are many threads about the tfsi packs on here as well, have a look and see what you think, i found Tufftys build thread very usefull for this up grade.

Thanks Phill
 
My money is on coil packs, autho still check your wiring.

If you have got the standard coil packs, ditch them for tfsi ones. I had a night mare with the standard packs failing and creating the exact same issue as you are getting. Awesome sell the tfsi coils and adaptor plates, and they are cheapest as well.
There are many threads about the tfsi packs on here as well, have a look and see what you think, i found Tufftys build thread very usefull for this up grade.

Thanks Phill

AGU has boltdown coils and an ignition amp so you would have to do an ICM delete to use push down coils...

<tuffty/>
 
Might be sounding a bit thick here but whats icm delete? Just checked coilpack wires and they seem to be fine. (head scratching)
 
Might be sounding a bit thick here but whats icm delete? Just checked coilpack wires and they seem to be fine. (head scratching)

Its a modification that removes the ignition control module (ICM, unit stuck to the side of the airbox) and allows you to run later bolt down or push down coil packs that have built in ignition amps and provide a better spark...

All the A4 boys wobble on about in the good ol' US of A...

<tuffty/>
 
Google would be a start ;P

...a few of the A4 (B5) members have also done this but 'ICM delete' in google will set you in the right direction..

<tuffty/>
 
Just to let u all know got my car back today amd they diagnosed the problem as been a block off pipe on the n75 valve needed putting onto the intercooler pipe as my waste gate wasnt doing anything. Put the pipe on now and you can see the waste gate opening and closing on throttle. Still need to test it with the engine under load tho. Thanks for all your help guys
 
Neither i just didnt connect it because i didnt think it would matter when i fitted my fmic