User Tag List

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old 03-27-2010, 04:15 PM   #1
Synyzter's Avatar
LS2 Power
 
Join Date: Sep 2007
Posts: 3,394
LS2 Power
 
Synyzter's Avatar
 
Join Date: Sep 2007
Posts: 3,394
Casino cash: $4615200
0.78 per day
Default p0171 and p0174

OK, so last week my truck was throwing these codes. I looked over all the vac lines, and everything was fine. Had the MAF tested and it was junk and causing my truck to stumble in the midrange. I cleared the codes and they stayed off. Now I replaced the MAF with a brand new stocker and added a CAI. The codes just keep coming back. All the hoses and lines on the intake are super tight and the MAF is perfectly fine. The only other thing I can think of is maybe its time to change the fuel filter? My truck has no rear cats, could the oxygen sensors finally have realized that they are missing (rears have been out for 4 months and a SES light never came on). As far as performance goes, everything seems normal. What are my possible problems before I wind up throwing money at shit I don't need?
__________________
2006 PBM GTO A4...G8 Sport Package 19s...Pacesetter 1-3/4 longtubes, 3in offroad mids, 2.5in catback...AEM Intake, ported LS2 manifold, ported LS2 Throttle Body...Drilled/Slotted Rotors...Pioneer Speakers...Bohnman Splitter...Lovells RR bushings and Poly Strut mounts...Lovells 0 drop springs...6000k HIDs in heads and fogs
Synyzter is offline   Reply With Quote
Old 03-27-2010, 05:22 PM   #2
Bob_Kurgan's Avatar
Flyin_Hawaiin
 
Join Date: Feb 2005
Posts: 3,013
Flyin_Hawaiin
 
Bob_Kurgan's Avatar
 
Join Date: Feb 2005
Posts: 3,013
Casino cash: $4611400
0.57 per day
Default

these are codes that will pop up with the CAI and no tune.. your car is running VERY lean now and i wouldnt go WOT without a tune.. you are living on limited time.

for these codes to pop up, your STFT have to exceed 25%, which means your truck is running at least 25% leaner then it should...
__________________
Built by Kurgan Motorsports
Tuned by Kurgan Motorsports
4.75 @ 152 on 275 D.R.

Living large in NE Georgia...
Bob_Kurgan is offline   Reply With Quote
Old 03-27-2010, 05:38 PM   #3
sleepercobra's Avatar  
Join Date: Aug 2009
Posts: 362
 
sleepercobra's Avatar
 
Join Date: Aug 2009
Posts: 362
Casino cash: $4694200
0.10 per day
Default

Quote:
Originally Posted by [email protected] View Post
these are codes that will pop up with the CAI and no tune.. your car is running VERY lean now and i wouldnt go WOT without a tune.. you are living on limited time.

for these codes to pop up, your STFT have to exceed 25%, which means your truck is running at least 25% leaner then it should...

this cant be good...
sleepercobra is offline   Reply With Quote
Old 03-27-2010, 11:19 PM   #4
Synyzter's Avatar
LS2 Power
 
Join Date: Sep 2007
Posts: 3,394
LS2 Power
 
Synyzter's Avatar
 
Join Date: Sep 2007
Posts: 3,394
Casino cash: $4615200
0.78 per day
Default

Quote:
Originally Posted by [email protected] View Post
these are codes that will pop up with the CAI and no tune.. your car is running VERY lean now and i wouldnt go WOT without a tune.. you are living on limited time.

for these codes to pop up, your STFT have to exceed 25%, which means your truck is running at least 25% leaner then it should...
they popped up before the CAI was even installed. i've made 1 WOT pass from 0-60 but other than that, i've been fairly light on the pedal to keep it safe. I'lll be pulling the blower off in 2 weeks to clean the intercooler, change the plugs, and changing the SC belt, and seeing if the PCV hose behind the blower is cracked. thats the only vacuum leak I can think of. I don't get why these trucks are so finicky. I see a million other people run CAI's with no tune and no issues.
Synyzter is offline   Reply With Quote
Old 03-28-2010, 05:06 PM   #5
Synyzter's Avatar
LS2 Power
 
Join Date: Sep 2007
Posts: 3,394
LS2 Power
 
Synyzter's Avatar
 
Join Date: Sep 2007
Posts: 3,394
Casino cash: $4615200
0.78 per day
Default

Well, fuel filter and MAF have been replaced. I can't find a vacuum leak anywhere, so it has to be the PCV hose behind the blower. thoughts?
Synyzter is offline   Reply With Quote
Old 03-28-2010, 06:25 PM   #6
SVTLSC's Avatar
Factory Freak
 
Join Date: Oct 2006
Posts: 2,790
Factory Freak
 
SVTLSC's Avatar
 
Join Date: Oct 2006
Posts: 2,790
Casino cash: $4610000
0.60 per day
Default

there are alot of things that can cause this. eventhough it sets a code and the fuel trims are off its not damaging anything because the computer is correcting it so it tuns fine. my truck throws them sometimes, i clear them and they go away for a while. Personally if it was me i would check to see what it was doin with a scan tool, watch the o2 sensors with a dvom and see what the fuel trims are at when it sets the code. also check the freeze frame see what temp, what the maf is reading when it does it. im not sure if the Ls have the ame problem but all the non supercharged 5.4L engines have a bad problem with the intakes leakin so that could be your prob too. Give me a call if you want i will help you out
__________________
PETER

96 Tahoe LS
95 Trans AM




Quote:
Originally Posted by The Pun View Post
Yeah, and your ugly and your mother dresses you funny.
SVTLSC is offline   Reply With Quote
Old 03-28-2010, 06:45 PM   #7
Bob_Kurgan's Avatar
Flyin_Hawaiin
 
Join Date: Feb 2005
Posts: 3,013
Flyin_Hawaiin
 
Bob_Kurgan's Avatar
 
Join Date: Feb 2005
Posts: 3,013
Casino cash: $4611400
0.57 per day
Default

Quote:
Originally Posted by SVTLSC View Post
there are alot of things that can cause this. eventhough it sets a code and the fuel trims are off its not damaging anything because the computer is correcting it so it tuns fine. my truck throws them sometimes, i clear them and they go away for a while. Personally if it was me i would check to see what it was doin with a scan tool, watch the o2 sensors with a dvom and see what the fuel trims are at when it sets the code. also check the freeze frame see what temp, what the maf is reading when it does it. im not sure if the Ls have the ame problem but all the non supercharged 5.4L engines have a bad problem with the intakes leakin so that could be your prob too. Give me a call if you want i will help you out
sorry, i have to disagree with you... generally with a stock maf, whatever correction is happening at lower maf voltage is also off that much at high maf voltages... so, with the change of a CAI, if the STFT and LTFT started correcting 15-25%, its linear on the rest of the maf transfer function..

If he is throwing these codes and there is an issue with the CAI requiring more fuel, he could possible hurt the motor by leaning it out at higher RPM.. I still suggest that it get taken to a reputable tuner and tuned for the newer mods.. MAF's are funny things and even looking at them funny can make some drastic issues.. Im not saying bring it to me, but bring it to someone to tune..
Bob_Kurgan is offline   Reply With Quote
Old 03-28-2010, 09:12 PM   #8
Synyzter's Avatar
LS2 Power
 
Join Date: Sep 2007
Posts: 3,394
LS2 Power
 
Synyzter's Avatar
 
Join Date: Sep 2007
Posts: 3,394
Casino cash: $4615200
0.78 per day
Default

Bob, you are the guy i'm going to have tune my truck. However, I had this issue before I even put the CAI on, thats why i'm trying to cover all the bases. only thing left is the PCV hose behind the blower that you can reach without taking the blower off. I'm looking to add a mafia and maybe a 6lber before I bring it to you for the final tune. no sense in spending all that tuning money for just a cai and a catback
Synyzter is offline   Reply With Quote
Old 03-28-2010, 09:14 PM   #9
Bob_Kurgan's Avatar
Flyin_Hawaiin
 
Join Date: Feb 2005
Posts: 3,013
Flyin_Hawaiin
 
Bob_Kurgan's Avatar
 
Join Date: Feb 2005
Posts: 3,013
Casino cash: $4611400
0.57 per day
Default

Quote:
Originally Posted by Synyzter View Post
Bob, you are the guy i'm going to have tune my truck. However, I had this issue before I even put the CAI on, thats why i'm trying to cover all the bases. only thing left is the PCV hose behind the blower that you can reach without taking the blower off. I'm looking to add a mafia and maybe a 6lber before I bring it to you for the final tune. no sense in spending all that tuning money for just a cai and a catback
all you need to do is get a propane torch and turn the gas on and run it around ANYWHERE you think a vacuum leak might be... if the RPM's jump, then you have found the leak... obviously, dont "light" the torch LOL.. jsut turn the gas on... i would also recommend brake cleaner, but that makes a mess.
Bob_Kurgan is offline   Reply With Quote
Old 03-28-2010, 09:25 PM   #10
Synyzter's Avatar
LS2 Power
 
Join Date: Sep 2007
Posts: 3,394
LS2 Power
 
Synyzter's Avatar
 
Join Date: Sep 2007
Posts: 3,394
Casino cash: $4615200
0.78 per day
Default

stupid question...but would i find that torch at ace hardware or something?
Synyzter is offline   Reply With Quote
Old 03-28-2010, 09:26 PM   #11
Bob_Kurgan's Avatar
Flyin_Hawaiin
 
Join Date: Feb 2005
Posts: 3,013
Flyin_Hawaiin
 
Bob_Kurgan's Avatar
 
Join Date: Feb 2005
Posts: 3,013
Casino cash: $4611400
0.57 per day
Default

like this

http://hand-tools.hardwarestore.com/...it-225466.aspx
Bob_Kurgan is offline   Reply With Quote
Old 03-28-2010, 09:36 PM   #12
Synyzter's Avatar
LS2 Power
 
Join Date: Sep 2007
Posts: 3,394
LS2 Power
 
Synyzter's Avatar
 
Join Date: Sep 2007
Posts: 3,394
Casino cash: $4615200
0.78 per day
Default

i figured thats what it was, just assuming i'd find it locally at a hardware store
Synyzter is offline   Reply With Quote
Old 03-28-2010, 09:39 PM   #13
Bob_Kurgan's Avatar
Flyin_Hawaiin
 
Join Date: Feb 2005
Posts: 3,013
Flyin_Hawaiin
 
Bob_Kurgan's Avatar
 
Join Date: Feb 2005
Posts: 3,013
Casino cash: $4611400
0.57 per day
Default

Quote:
Originally Posted by Synyzter View Post
i figured thats what it was, just assuming i'd find it locally at a hardware store
yes, i was just showing a picture of what you need to get
Bob_Kurgan is offline   Reply With Quote
Old 03-28-2010, 09:42 PM   #14
Synyzter's Avatar
LS2 Power
 
Join Date: Sep 2007
Posts: 3,394
LS2 Power
 
Synyzter's Avatar
 
Join Date: Sep 2007
Posts: 3,394
Casino cash: $4615200
0.78 per day
Default

Quote:
Originally Posted by [email protected] View Post
yes, i was just showing a picture of what you need to get
lol. well thank you. hopefully I can get this issue sorted out and the truck functional enough for a dyno tune
Synyzter is offline   Reply With Quote
Old 03-28-2010, 09:43 PM   #15
Bob_Kurgan's Avatar
Flyin_Hawaiin
 
Join Date: Feb 2005
Posts: 3,013
Flyin_Hawaiin
 
Bob_Kurgan's Avatar
 
Join Date: Feb 2005
Posts: 3,013
Casino cash: $4611400
0.57 per day
Default

Quote:
Originally Posted by Synyzter View Post
lol. well thank you. hopefully I can get this issue sorted out and the truck functional enough for a dyno tune
sounds good.. just let me know if we can help.

thanks
Bob_Kurgan is offline   Reply With Quote
Old 03-30-2010, 07:55 PM   #16
SVTLSC's Avatar
Factory Freak
 
Join Date: Oct 2006
Posts: 2,790
Factory Freak
 
SVTLSC's Avatar
 
Join Date: Oct 2006
Posts: 2,790
Casino cash: $4610000
0.60 per day
Default

Quote:
Originally Posted by [email protected] View Post
sorry, i have to disagree with you... generally with a stock maf, whatever correction is happening at lower maf voltage is also off that much at high maf voltages... so, with the change of a CAI, if the STFT and LTFT started correcting 15-25%, its linear on the rest of the maf transfer function..

If he is throwing these codes and there is an issue with the CAI requiring more fuel, he could possible hurt the motor by leaning it out at higher RPM.. I still suggest that it get taken to a reputable tuner and tuned for the newer mods.. MAF's are funny things and even looking at them funny can make some drastic issues.. Im not saying bring it to me, but bring it to someone to tune..
ok makes sense. ive never tried that propane trick will have to try that. i usually use a water spray bottle and when it starts to miss you find it
SVTLSC is offline   Reply With Quote
Old 03-31-2010, 02:17 PM   #17
Synyzter's Avatar
LS2 Power
 
Join Date: Sep 2007
Posts: 3,394
LS2 Power
 
Synyzter's Avatar
 
Join Date: Sep 2007
Posts: 3,394
Casino cash: $4615200
0.78 per day
Default

OK, so once again today, I decided to go over the p0171 codes and the p0174. Today, only the p0171 code showed up. I checked all the vacuum lines including the one behind the blower. No leaks. The MAF and fuel filter are brand new, as well as the CAI (was throwing code before intake).

Now, for 4 months i had no rear cats into the stock exhaust with no problems or codes. I put a muffler on to replace the stocker. The day after I put the muffler on, roughly 2 or 3 drive cycles of 1+ hours, the SES light came on with these codes. Now, if my thinking is correct, is it possible that the increased flow of the muffler finally triggered the rear o2 sensors to falter from the lack of rear cats, thus causing the truck to think its lean?
Synyzter is offline   Reply With Quote
Old 04-03-2010, 08:40 PM   #18
Bob_Kurgan's Avatar
Flyin_Hawaiin
 
Join Date: Feb 2005
Posts: 3,013
Flyin_Hawaiin
 
Bob_Kurgan's Avatar
 
Join Date: Feb 2005
Posts: 3,013
Casino cash: $4611400
0.57 per day
Default

glad i could help
Bob_Kurgan is offline   Reply With Quote
Old 04-03-2010, 09:13 PM   #19
SVTLSC's Avatar
Factory Freak
 
Join Date: Oct 2006
Posts: 2,790
Factory Freak
 
SVTLSC's Avatar
 
Join Date: Oct 2006
Posts: 2,790
Casino cash: $4610000
0.60 per day
Default

no cats wont set a lean code. it would set a p0420 or 430, or one for o2 sensor cycing
SVTLSC is offline   Reply With Quote
Old 04-03-2010, 09:22 PM   #20
Synyzter's Avatar
LS2 Power
 
Join Date: Sep 2007
Posts: 3,394
LS2 Power
 
Synyzter's Avatar
 
Join Date: Sep 2007
Posts: 3,394
Casino cash: $4615200
0.78 per day
Default

thanks bob!
Synyzter is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -5. The time now is 05:13 AM.


Powered by vBulletin® Version 3.8.1
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
SEO by vBSEO 3.6.0
User Alert System provided by Advanced User Tagging v3.0.6 (Lite) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
no new posts