ok so i bought my car round 7 months ago, when i got the car the cel light was on! it had 125k. the wastegate was bad so i replaced it. very randomly it started to run very very badly i was told it was my exhust so i put a cat del on, that did not help. the real prob was the ignition mod. so i replaced it and it still ran shty bc the cat del. i went to see why my cel light was on and the car was throwing 12 codes, 4 of the codes were the same. i was told that you cant put a cat del on without a chip..or non-foulers i tried the non-foulers that didnt work. i checked all my fuses the engine timeing fuse was blowing every time i turned the car on. well i had no idea why but one day it just stoped doing that and that is fine. i put the cat back on because i thought that since those probs fixed that the only thing makeing it run crappy was the cat del. when i put it back on it continued to run crappy so i went to have the cel light cheacked again (i cleared the codes 2 days prior) and it was throwing the following codes

p1472
p0102
p1425
p0134
p1169 pending
p1198 pending
p0140 pending

somewhere during all that i replaced the sparkplugs n maf.
all this was bout 3 months ago and just the other day the cel light went off i thought the light mab burnt out so i had it checked again and there were no codes, (during that 3 months i did nothing to the car!!).
but my ? is why is it still detinating when i give it less than half throtle?????

 

just a word to the wise, it is looked down upon posting random codes without meaning, dont know if you know how to look them up or not. http://www.obd-codes.com/trouble_codes/audi/ that site is for audi specific codes, which is anything p1xx in your case. the ones that are p0xx are the same for all cars cause they are government mandated. with that said i took the liberty of looking them up for you.
P1472 EVAP Emission Contr.LDP Circ Short to Ground
P1425 Tank Vent.Valve Short to Ground
i think you mean "p1196' not "p1169" there is no such code for audi.
P1196 O2 Sensor Heater Circ.,Bank1-Sensor1 Electrical Malfunction
P1198 O2 Sensor Heater Circ.,Bank1-Sensor2 Electrical Malfunction
p0102 is maf sensor low output
p0140 is 02 sensor no activity detected (bank 1, sensor 2)
clearly, you had an issues with your 02 sensors. did you replace the 02 sensors when you put the test pipe on?

 

i already knew what they were i just figurd since i was on a audi forum that i wouldnt have to list all that! my bad. yes i know i had an prob with my o2 sensors no i did not replace them i put a non-fouler in i switched the cat before i tried replaceing the 02's but as i stated there are no codes anymore and i dont know why. i quit trying to fix it after i put the cat back on which was a month or so ago. i did mean p1196. i am currently using the orignal cat, i was told that if the exhust is cut that it will run roughly because of that, but it has the same prob it did before i replaced the cat. and my ignition mod is fine.

 

the reason the codes went away on their own is because you put the cat back in and the car figured it out, after a while anyways. i would first try resetting the ecu by disconnecting the negative lead on your battery for a minute or two (only do this if you have your radio code, or an aftermarket unit installed). its a long shot, but i always try to go for the simple stuff first. it usually costs less. when you fixed your wastgate, did you take the turbo out completely? i would check for exhaust leaks around that area too. also, what are your boost levels?

 

i know but the cel was on way before i bought the car. and all i did was replace the cat, maf, ignition mod, and waist gate. it started running so much better a month or so after i put the test pipe in. and i figured since it wasn't "backfiring" as bad that what ever i did fixed it so i put the cat back on thinking it wouldnt backfire any more. ( i was told that my car would never run right with a test pipe with out a chip or my comp reprogrammed.) i honestly am very confused about the whole thing! lol. i have worked on a lot of cars and have had a lot of cars and never came across something like this, granted this is my first audi. i will try i tried that before but it didnt do anything, but it wont hurt to do it again. yes i did take it completely out. i was wondering if it could be a boost prob..over boosting mab. i have no clue what my boost levels are im waiting for my Gage to get in. could it be a fuel + air prob? i am sorry if i am confusing you. im just very aggravated and confused myself.

 

it is possible to run a test pipe without reprogrammin. the computer doesnt know if you have a cat in. you will get cel's, especially without nonfoulers, but from what ive heard they dont effect performance. get a boost gauge and post readings. they help a ton. odds are it isnt overboosting, but it is possible if you didnt replace the wastegate properly and didnt set it right. get a boost gauge in there and it would help more.

 

will do, but my cel light came back on yesterday and it said cyl 2 misfire should i replace the coil pack? i already replaced the spark plugs.

 

hold off on the coil pack for a while. you can do the simple test of switching that coil pack to another non-misfiring cylyinder and if that cylinder starts to misfire you would know it was a bad coil pack then.

 

you did not put a non fouler on the primary O2 sensor correct?

if they are stock O2 sensors, you need to replace both of them because they are not working correctly. if the heater circuits are not operating then the plugs will not get up to temperature and give accurate readings.

you should figure out why that is happening, one of the sensors probably has a short to ground and needs to be replaced. it stopped blowing the fuse probably because the short burned itself out and now its just a completely open circuit.

 

now my abs light is on and my break light is blinking. the fuse is fine now. and i am not using the test pipe any more and im not throwing any o2 codes should i still replace them??

i will do the coil pack test tomorrow...and the boost Gage and post when im done


thanks!!