OBD II pros come in.

[shonoff24]

Hey all, I just picked up a 96 Talon Tsi AWD A/T about 10 days ago.........Its not been running right for 8 of them............Sometimes the car will run absolutely perfect, and I will shut it off for a few minutes then restart it, and it runs horrible. It misses so bad that it will hardly even go down the road. Sometimes when its running bad, it will all the sudden just start running great...........It only seems to be doing it while the engine is up to temp, or partially up to temp.............Im getting a consistant CEL every time it runs bad. It is throwing a P0202 every time. Sometimes it throws a P0302 with it, and sometimes it throws a P0170 with them..............The fuel injectors, spark plugs, plug wires, and upstream 02 sensor have been checked and are ok. I put noid lights on the injector harness and its getting a signal..............So Im running out of ideas on this and it would be greatly appreciated if someone could point me in the right direction. Thanks in advance.

 

[FORMONTOYA]

P0202 = Injector Circuit Malfunction - Cylinder 2
P0302 = Cylinder 2 Misfire Detected
P0170 = Fuel Trim Malfunction (Bank 1)

http://autorepair.about.com/cs/troubleshooting/l/bl_obd_main.htm

Car profile?
Obviously somethings amiss with cylinder 2.
P0170..........there is a "tolerance" built into the fuel trims to compensate for variances in load conditions, if the car stays "pegged" at one end or the other for a certain period (IDK what that is), it will throw this code. Could be a result of the previous 2.

 

[Auto RS T]

From my experience the P0170 is most likely a result of the other two codes. Like (Formontoya) mentioned. The codes on the top of the list are the priority.

Check the connections on the injector harness again. From these codes I would re-focus at looking into the wiring related to the number 2 injector. Making sure that the harness is making a good connection and the wiring is not compromised furthur down the line.

If this were my car and I was getting desperate, I would swap injectors and see if the code will move to another cylinder. I know it is cavemanish but it would definatley rule out the #2 injector if the problem persist. (even though the P0302 is second on the list and could be induced by the P0202) The injector swap is just too easy not to try it out.

 

[shonoff24]

From my experience the P0170 is most likely a result of the other two codes. Like (Formontoya) mentioned. The codes on the top of the list are the priority.

Check the connections on the injector harness again. From these codes I would re-focus at looking into the wiring related to the number 2 injector. Making sure that the harness is making a good connection and the wiring is not compromised furthur down the line.

If this were my car and I was getting desperate, I would swap injectors and see if the code will move to another cylinder. I know it is cavemanish but it would definatley rule out the #2 injector if the problem persist. (even though the P0302 is second on the list and could be induced by the P0202) The injector swap is just too easy not to try it out.

Did that...................... swapped the no. 2 & no. 4 injectors....................problem stayed in no 2 cylinder

 

[perley03]

From my experience the P0170 is most likely a result of the other two codes. Like (Formontoya) mentioned. The codes on the top of the list are the priority.

Check the connections on the injector harness again. From these codes I would re-focus at looking into the wiring related to the number 2 injector. Making sure that the harness is making a good connection and the wiring is not compromised furthur down the line.

If this were my car and I was getting desperate, I would swap injectors and see if the code will move to another cylinder. I know it is cavemanish but it would definatley rule out the #2 injector if the problem persist. (even though the P0302 is second on the list and could be induced by the P0202) The injector swap is just too easy not to try it out.

Had the same problem with my Dakota. Always flashing a code atleast once a week. Always cylinder 3. I changed everything spark related, same thing. So i swapped injectors, now moved to that cylinder. Found out i had a faulty injector, so i replaced it and no problems in the past 5 weeks.
If it is the same cylinder, even though you swapped injectors, i would be doing a compression check and a leak down test in that cylinder. There is a reason why you are getting a misfire, and compression might have a thing to do with it.