P0505 and P0170

[twinkiemobile]

Ok, so i've searched. this is what i gather
P0505 ISC malfunction. you can test it. when you press the clutch rpm goes down to the point where car almost stalls. connected to throttle body by 2 8mm bolts.
P0170 Fuel trim malfunction. most times the front o2 sensor. can be checked by date logging voltage when throttle is pressed or something like that.

Well here's the odd thing. i erased the codes. and the CEL came back again(i was expecting it) however the P0170 code was gone and still has not returned.

I still have the P0505 and i was going to continue driving around and see if i still had my poor mileage. however, it seems that when i drive my car it would sputter as if i had some sort of sever boost leak. but i've checked all my pipes and they all look good. Would the ISC have something to do with tripping out the car to make it sputter at high RPMS?
I'm pretty sure that my only option is to replace my ISC, i've already sourced the parts either on Ebay or a repectable recylcling place here in the bay area. which should i go for? thanks in advance for any help you guys can give.

- Jose

 

[TRBOBLU]

Well for the P0505 youll want to buy a new or used ISC. Its a very common problem for those to go dead. I cant see how the ISC would affect the high end sputter you talked about because it just controls the idle. The P0170 is tricky. Most of the time from what Ive seen or heard its a bad O2 sensor. Can you describe the sputter more? Other things can cause this code to occur like a malfuctioning airflow sensor, bad coolant temp sensor, bad intake air temp. sensor, or a bad barometric sensor, a bad injector, and of course a boost leak of some sort. A service manual can tell you how to test the sensors. You said you checked the pipes and they looked good, does that mean you did a boost leak test or just visually inspected them? Im curious because a boost leak was the cause of my car throwing the code years back. Id check the things I listed and if the problem still occurs send me a message and Ill try to help out more.

 

[BISHILVR]

Pushing the clutch in should'nt affect the rpm's to that point anyway. You should check your crankshaft end play to make sure you dont have a thrust bearing failing.

 

[twinkiemobile]

Well, as for the sputter like effect. it feels as if the car will build boost. and then suddenly it will have a really hard jerk. I'm going to rent out the scanner again tomorrow and maybe there's going to be another code. As for the ISC i'm pretty sure that that's the cause because reading through other peoples experiences i'm coming out with the same results. poor idle, etc. etc. I visually check all the pipes. took them apart. cleaned the couplers/clamps and reinstalled them. all looked good. maybe a leak on the intake mani or tb? i don't know, i'm going to run another scan and keep you guys updated. thanks

- Jose

 

[Erok]

ill ship you a spare isc if u want i have several of them, to tell you the truth i replaced one on a 92 talon about 2 hours ago, car was trying to die easy diagnosis, slaped on one of my spares in like 5 mins, and fixed the car, to test your isc just unplug it and it should stop dieing but your car will adjust rich and spit alil carbon
good luck bro
30 shipped= working isc, let me know


sleepygsx

 

[twinkiemobile]

30 dollars for a working ISC. kool. for a 2g right? anyway, will using my car with the ISC acting up cause any problems with normal driving such as gas mileage etc.? thanks. i'll also PM you, PM me with your paypal.

- Jose