'99 z71 oxygen Sensor or Bad Vaccum Hose Help?
#1
CF Beginner
Thread Starter
Join Date: Jan 2008
Location: Louisiana
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
![Default](/forum/images/icons/icon1.gif)
I bought my truck and took it to Autozone and they put it on the computer.. b/c my check engine light is on..and once in a while my ABS and parking brake comes on..They got back 4 codes..one saying myoxygen sensor could be out or I have a defective vaccum hose..they said if it's my oxygen sensor it will clear everything up..but if it's a bad hose we have to find which one it is..and replace it and it will clear everything up..they could hear a hissing comming from the engine but couldn't tell us which one..they said that with a bad hose it can make everything go crazy..the truck runs great no problems b/c the securtiy box isn't flashing or going off..They say it's nothing major..but still I want to find my problem..( I wonder if this can cause the cruise control not to work as well..I believe I have a blown fuse..) anyways They also said this is causing the truck to run lean..also one of these print out says a knock sensor. So pretty much let me straightin' this out.. ![EEK!](https://chevroletforum.com/forum/images/smilies/eek.gif)
[ol][*]Check System light stays on. Once in a while ABS and Parking brake lights come on.[*]the abs and parking lights go off when i kill the truck and come on at random times.[*]Codes : P0308 ( Cylinder Misfire in cylinder 8 ) P0171 ( Fuel trim bank one condition or oxygen sensor ) P0507 ( IAC circuit condition or Idle speed higher or lower then expected ) P0332 ( Knock sensor condition )[*]P0308,P0507,P0332 - They are are being caused by a bad hose.[*]P0171 - Is caused by oxygen sensor [/ol]
So Next week I'm gonna take it to a mechanic..and see how much they are going to charge a girl to look at her truck.. " I'm sure they will be like OoOo a woman, She won't know crap! lets charge her at the A$$!" Let's just say they are going to have their hands full *lol*![Big Grin](https://chevroletforum.com/forum/images/smilies/biggrin.gif)
Ps. as for the cruise control..would anything else be causing it not to work? it just won't come on period..
Anyways sorry for the long message!
Hope one of you "Chevy Lovers" can help me!
![EEK!](https://chevroletforum.com/forum/images/smilies/eek.gif)
[ol][*]Check System light stays on. Once in a while ABS and Parking brake lights come on.[*]the abs and parking lights go off when i kill the truck and come on at random times.[*]Codes : P0308 ( Cylinder Misfire in cylinder 8 ) P0171 ( Fuel trim bank one condition or oxygen sensor ) P0507 ( IAC circuit condition or Idle speed higher or lower then expected ) P0332 ( Knock sensor condition )[*]P0308,P0507,P0332 - They are are being caused by a bad hose.[*]P0171 - Is caused by oxygen sensor [/ol]
So Next week I'm gonna take it to a mechanic..and see how much they are going to charge a girl to look at her truck.. " I'm sure they will be like OoOo a woman, She won't know crap! lets charge her at the A$$!" Let's just say they are going to have their hands full *lol*
![Big Grin](https://chevroletforum.com/forum/images/smilies/biggrin.gif)
Ps. as for the cruise control..would anything else be causing it not to work? it just won't come on period..
Anyways sorry for the long message!
![Smile](https://chevroletforum.com/forum/images/smilies/smile.gif)
#3
![Default](/forum/images/icons/icon1.gif)
It would help if we knew the year, type and engine of your truck?
And also any details such as the current miles?
Did this happen all of a sudden or did these problems occur in an instance?
What are the drivability symptoms?
What maintenance been done in the last year?
Is it also safe for us to assume that all the filters are good and the truck has had ALL the proper regular scheduled maintenance competed in a timely manner?
I would say that there is definitely a vacuum leak somewhere, the most likely source is a bad intake manifold gasket and I am not so sure that is the only problem.
And also any details such as the current miles?
Did this happen all of a sudden or did these problems occur in an instance?
What are the drivability symptoms?
What maintenance been done in the last year?
Is it also safe for us to assume that all the filters are good and the truck has had ALL the proper regular scheduled maintenance competed in a timely manner?
I would say that there is definitely a vacuum leak somewhere, the most likely source is a bad intake manifold gasket and I am not so sure that is the only problem.
#4
![Default](/forum/images/icons/icon1.gif)
You need a tune up. P0308 means that cyl. 8 is misfiring, and that really could be the cause of all the other issues. I'd start with replacing all the spark plugs, and wires if it has any, then clear the codes and see if that fixes it.
#5
CF Beginner
Thread Starter
Join Date: Jan 2008
Location: Louisiana
Posts: 4
Likes: 0
Received 0 Likes
on
0 Posts
![Default](/forum/images/icons/icon1.gif)
The tune up my husband figured is what we needed.. it's a '99 silverado Z71 V8 Vortec also has 280,000 miles, it drives good it doesn't sludge or splurge or nothing it doesn't act up... I just bought it 3 days ago and i called the dealer and told them this.. and the salesman was like it's probably a sensor out..or oxygen sensor..( which i'm sure they knew about it and didn't want to tell us ) all it does is has the check engine light on all the time..and then at random times the ABS and parking brake light comes on and stays on till i kill the truck..
pontiacmrc1 - We are gonna get a tune up done come next week.
ZX1100F1 - yeah the guy said he heard a hissing comming from under the intake manifold. Now if we can just find which hose it is? I guess I can use soapy water huh? or do is there another way i can do it?
Thanks for the replys and help!
pontiacmrc1 - We are gonna get a tune up done come next week.
ZX1100F1 - yeah the guy said he heard a hissing comming from under the intake manifold. Now if we can just find which hose it is? I guess I can use soapy water huh? or do is there another way i can do it?
Thanks for the replys and help!
![Big Grin](https://chevroletforum.com/forum/images/smilies/biggrin.gif)
#6
![Default](/forum/images/icons/icon1.gif)
With those codes and the age and mileage on the motor it needs much more then a simple tune-up although a new set of plugs and a thorough fuel injector system cleaning would be a good place to start, although I would take an OHM reading on the (high tension) plug wires before I decided to replace them, if any wire reads over 30,000 ohms then replace them all.
Bad intake manifold gaskets (can make a hissing noise) and is a common problem on these engines (I'm going to guess that you have a 1500 model with either a 4.8L or 5.3L V8), there are very few vacuum hoses on these engines and they are very easy to remove and inspect.
There are also two places where the ground leads can come loose or corrode, one is the Electronic Brake Control Module (EBCM) underneath the drivers door on the frame, look for the heaviest gauge ground wire that is attached to the frame and unbolt it, use a wire wheel to thoroughly clean the contacts and replace the bolt/nut and washer with like sizes and tighten it all down, this could solve your ABS and Park light.
Another ground wire is on the passenger side head of the engine, at the front just below the plastic oil spout, basically you want to remove the hardware and clean everything up and put it back together, this can cure some of your other DTC's.
Dump Six 12oz bottles of Chevron Techron fuel system cleaner in a full tank of gas and run it out, this does a remarkabe job at cleaning things up.
Dave
Bad intake manifold gaskets (can make a hissing noise) and is a common problem on these engines (I'm going to guess that you have a 1500 model with either a 4.8L or 5.3L V8), there are very few vacuum hoses on these engines and they are very easy to remove and inspect.
There are also two places where the ground leads can come loose or corrode, one is the Electronic Brake Control Module (EBCM) underneath the drivers door on the frame, look for the heaviest gauge ground wire that is attached to the frame and unbolt it, use a wire wheel to thoroughly clean the contacts and replace the bolt/nut and washer with like sizes and tighten it all down, this could solve your ABS and Park light.
Another ground wire is on the passenger side head of the engine, at the front just below the plastic oil spout, basically you want to remove the hardware and clean everything up and put it back together, this can cure some of your other DTC's.
Dump Six 12oz bottles of Chevron Techron fuel system cleaner in a full tank of gas and run it out, this does a remarkabe job at cleaning things up.
Dave
Trending Topics
#8
![Default](/forum/images/icons/icon1.gif)
find the vacuum hose that is leaking.
this will fix everything including your cruise control. and if i were you, i'd start checking the hoses around the cruise control.
A bad vacuum hose will allow the motor to suck in too much air and cause it to run lean. A lean mixture will cause a misfire. A misfire can dump raw fuel into the exhaust causing your O2 sensor to not work properly, which in turn turns on the check engine light. And the cruise is most like vacuum operated, and with a leak, will not operate as desired. And while you're under the hood, check the level of the brake fluid. If it is borderline low, when you turn corners, it may cause it to go low, turning on the red brake light on the dash, which in turn will cause the amber ABS light to turn on, disabling the ABS system because of low fluid.
this will fix everything including your cruise control. and if i were you, i'd start checking the hoses around the cruise control.
A bad vacuum hose will allow the motor to suck in too much air and cause it to run lean. A lean mixture will cause a misfire. A misfire can dump raw fuel into the exhaust causing your O2 sensor to not work properly, which in turn turns on the check engine light. And the cruise is most like vacuum operated, and with a leak, will not operate as desired. And while you're under the hood, check the level of the brake fluid. If it is borderline low, when you turn corners, it may cause it to go low, turning on the red brake light on the dash, which in turn will cause the amber ABS light to turn on, disabling the ABS system because of low fluid.
#9
![Default](/forum/images/icons/icon1.gif)
my cousin has aproblem with his car's oxygen sensor, with your discussion, It helps me to advice my cousin what's the best thing to do.
#10
![Default](/forum/images/icons/icon1.gif)
i no these were posted a long time ago but for those having similar problems. abs and brake light, check the brake cables going to rear wheels, they are just riding on a hook to hold them in place, and mine slipped out and wore a whole in the cable. Other issues, tune up first and also take part throttle body and clean it the flap gets sticky,and take idle air control valve also and clean, to much carbon build up, then get some sea foam pour 1/3 of the bottle into the power brake booster hose, when its running, shut it off, wait 5 min, start it back up, burns the rest of the carbon out. it will smoke like crazy but it needs to get the carbon out.
Thread
Thread Starter
Forum
Replies
Last Post