Trouble codes p0171 p0102 p1153

**redbird555** · 02-22-2010, 04:37 PM

Well the other day I got an ses light on I had p1153 and p0102 so I cleaned the maf and tossed my k&n filter drove the car and all was good no codes. I drove the car back to college ie 200 miles and once i got into the parking lot it started to run badly with a handheld I had code p0171 pop up and for just a split second p0301 which went away so p0171 was there my maf appeared to be working fluctuating with throttle and idling at abt .78 lb/m fluctuating a small bit of course. The o2 sensor on that side is a pretty new bosch sensor which I suppose could be an issue looking at the computer it sits at about .015-.025v while the other sensor is fluctuating and working as it should. I would think if this was a maf issue I would be throwing codes on both sides but I'm not could this be a sensor issue.
Thanks Dan

**35th-ANV-SS** · 02-22-2010, 04:48 PM

Could possibly be a vacuum leak, which would cause a lean condition (your P0171) code, and make cylinder one misfire (P0301).

**redbird555** · 02-22-2010, 05:06 PM

Thanks I was going to check that out too I briefly looked it over and didnt notice anything out of the ordinary i redid all the pcv connections a few months back with quality hose but ill give it a look sat when I have time.Its kinda weird that te car ran fine on the highway and as soon as I shut it off for a sec it started running like crap I'd think a vac leak would have been more gradual and or made it idle a little high? Btw the p0301 code went away I think it was due to the fact of all the fuel being dumped in. Is there any way to completely rule out the maf other than its only throwing one bank code?

**35th-ANV-SS** · 02-22-2010, 07:11 PM

Read my post in this thread on how to check the MAF

http://www.ls1.com/forums/showthread.php?t=131375

**redbird555** · 02-23-2010, 04:38 AM

Thanks 35th I'll give it a try on Sat because I'm busy with school all this week. The car runs very rough when in closed loop but actually runs ok in open loop idk if that helps though. I think it may be possible my maf is failing especially after it threw p0102 and now this code 171 after that one was cleared. The only other thing i could think of is when I was installing my o2 extensions I broke a wire and had to solder it back together then heat shrink it so I suppose I should check that extension lol. Just wondering though if the maf had failed wouldnt it be throwing a p0174 for the other side or can a maf just throw a code for one bank?

**redbird555** · 02-23-2010, 05:35 AM

Ok dont think its a vac leak my friend went out to start my car and while he didnt do the screwdriver test he did start the car up. And noticed while in open loop the car runs fine but as soon as it switches to closed loop it begins to miss heavily.......MAF or o2's?

**35th-ANV-SS** · 02-23-2010, 08:57 AM

The computer only uses the information from the O2 sensor in closed loop, and being that you are only getting a code for the one bank, I would start by checking the wiring on that O2 sensor.

**redbird555** · 02-23-2010, 09:04 AM

Ok well i just tried a few things and Im 90% sure the maf is fine its reading correctly and amazingly the car is running just fine no codes etc. The bellow behind the MAF was not clamped tho and may have been causing some kind of leak, however I still think the problem lies with he o2 sensor. When I had the scan tool hooked up I could see the sensor operating normally then for some unknown reason the voltage on the sensor would drop to 0 and remain low for a few secs then come back and fluctuate normally I dont have time to work on it today but atleast the cars running correctly now and I can drive it as little as I need to until I get time.One other thing I noticed is that I bought the headers and extensions used and on the problem side the connection had been soldered together on one wire could this be the issue?? This is a bosch sensor and after hearing the problems people have ill be going corvette denso on the next ones.

**35th-ANV-SS** · 02-23-2010, 09:08 AM

Originally Posted by redbird555

Ok well i just tried a few things and Im 90% sure the maf is fine its reading correctly and amazingly the car is running just fine no codes etc. The bellow behind the MAF was not clamped tho and may have been causing some kind of leak, however I still think the problem lies with he o2 sensor. When I had the scan tool hooked up I could see the sensor operating normally then for some unknown reason the voltage on the sensor would drop to 0 and remain low for a few secs then come back and fluctuate normally I dont have time to work on it today but atleast the cars running correctly now and I can drive it as little as I need to until I get time.One other thing I noticed is that I bought the headers and extensions used and on the problem side the connection had been soldered together on one wire could this be the issue?? This is a bosch sensor and after hearing the problems people have ill be going corvette denso on the next ones.

I personally feel that the problems you've been hearing about the Bosch O2 sensors failing are probably the result of people not having a proper tune and hence the O2 sensors failing prematurely due to running rich.

Definitely sounds like something going on with the wiring perhaps.

Also, if your bellows was loose AFTER the MAF, this would be letting unmetered air into the intake, which would cause your lean condition.

Good luck and let us (me) know if your SES lights stay off now that you've tightened that up nice and snug.

**redbird555** · 02-23-2010, 09:40 AM

OK will do although I probably wont be driving it much lol until I have to drive home in a week from college. I did drive it abt 30 miles after the bellow and all was good I just cant figure out why it drops to 0 volts at some pts?

**redbird555** · 02-24-2010, 02:44 PM

hey guys the car is still driving like normal but the scanner just showed Closed loop fault bank 1. Does anyone know what this means its not a code and no ses light the o2 sensor on that side still dips down low while the other doesnt however it goes back up to normal readings after a sec, just wondering if it may cause that.

**35th-ANV-SS** · 02-24-2010, 02:46 PM

Originally Posted by redbird555

hey guys the car is still driving like normal but the scanner just showed Closed loop fault bank 1. Does anyone know what this means its not a code and no ses light the o2 sensor on that side still dips down low while the other doesnt however it goes back up to normal readings after a sec, just wondering if it may cause that.

Is this the same sensor you soldered? Might have something to do with it...not sure.

**redbird555** · 02-24-2010, 05:09 PM

yep it is im thinking that since its soldered it may be causing some interference problems making the sensor act all weird

**redbird555** · 02-24-2010, 05:23 PM

one more thing the post cat o2 sensor is not hooked up on that side (wire wasnt long enough to reach with the new y pipe) although its there in the y pipe while the other side is actually hooked up into the harness and working its just not doing much because we tuned it out. Could this cause the fault in closed loop.