2002 Subaru Impreza 2.5Rs 190xxx miles automatic. Code p1515 is on and car is running really bad. Replaced aic and it didn’t work. Any suggestions? It also gave multiple cylinders misfire. Replaced all spark plugs,wires and coil. Still the same
That thing is so old the poor running could be a lot of things, including internal engine problems.
The P1515 can be caused by electrical circuit problems as well as a fault in the AIC itself. Did you test the IAC valve and the circuit before replacing the part? Was the replacement an OEM part?
https://www.autocodes.com/p1515_subaru.html
How old are your air and fuel filters? What diagnostic steps have you taken so far? Checked live data for problems? Checked for a blown head gasket? (As you likely know those engines are prone to head gasket failure.) Vacuum leaks? Tested MAF sensor and upstream O2 sensor? Performed a compression or leakdown test? Tested fuel pressure? How old is your timing belt, could it have skipped a tooth?
You can find an online repair manual for that car here which may help:
https://charm.li/Subaru/2002/Impreza%202.5%20RS%20Sedan%20AWD%20F4-2.5L%20SOHC/
You might also check the troubleshooting section of the site FAQ.
Also, for future reference when posting please put the details of your topic in the body of your post, not the title line which is meant for a short description. Thank you.
