Smog test fail
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,674
Likes: 4,094
From: Cape Coral, Florida
So it says your (MIL) "check engine light" is on...you have a P0171 or P0174 (bank 1/2 system lean) or both AND a random misfire (P0300) !!!...a trusted diagnostic repair shop should be able to sort this out !!
Last edited by C5 Diag; Oct 31, 2019 at 12:13 PM.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Some QUESTIONS??????
Are you willing and able to troubleshoot and repair your C5??
What mechanical skills do you have or can you get somebody to help with?
Tools??
When was the last time you have plugs and wires replaced. Vacuum line intact and connected???
Are you willing and able to troubleshoot and repair your C5??
What mechanical skills do you have or can you get somebody to help with?
Tools??
When was the last time you have plugs and wires replaced. Vacuum line intact and connected???
Thread Starter
Heel & Toe
Joined: Aug 2016
Posts: 19
Likes: 0
From: Las Vegas Nevada
Thread Starter
Heel & Toe
Joined: Aug 2016
Posts: 19
Likes: 0
From: Las Vegas Nevada
I have a repair shop, I do not have skills to do them myself. I have no record of the wires and plugs being changed. Vacuum line intact is a good question that I will ask them. Thank you!
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Pro
Joined: Aug 2007
Posts: 599
Likes: 39
From: citrus heights ca
if Bill is offering his time i would definitely give him a call. him and c5 diag probably know more about these cars than everyone else here combined
before you call him you might want to write down all the codes you have.this videos shows how to find them
before you call him you might want to write down all the codes you have.this videos shows how to find them
Last edited by jonnyc; Oct 31, 2019 at 09:46 PM.
Melting Slicks
Joined: Aug 2013
Posts: 2,491
Likes: 315
St. Jude Donor '15-'16-'17-'18-'19-'20-'21-'22
Please note that you might not be able to take the smog test right away after having your car repaired. Depending on what work was done, there is a possibility that you will have to do a drive cycle as outlined in the link below. Just a heads up so you don't show up at the smog test station and they tell you that your car is not ready to take the test.
Pro
Joined: Nov 2018
Posts: 675
Likes: 102
system to lean :
listen to everything Bill suggests you do
I just had my car in for a smog check . it was running lean like yours. there is a short hose going to a pvc valve behind the throttle body. mine was leaking from that hose. You have a vacuum leak somewhere
listen to everything Bill suggests you do
I just had my car in for a smog check . it was running lean like yours. there is a short hose going to a pvc valve behind the throttle body. mine was leaking from that hose. You have a vacuum leak somewhere
Thread Starter
Heel & Toe
Joined: Aug 2016
Posts: 19
Likes: 0
From: Las Vegas Nevada
Hi Bill, thank you so much for the offer to call and help me over the phone. I hear you are the man when it comes to Corvettes and I so appreciate the offer of your time.
I am in a bit of a time crunch, going out of town soon, car needing registered before I leave, thus it must get repaired. I'm sorry I just didn't have time to take advantage of your call and expertise. I did take it in and it needed a tune up, and everything else you said it needed. Wow, so glad I had that info going in, thank you, again! She has 124,000+ miles on her, so it was definitely time.
See you on the CorvetteForum!
I am in a bit of a time crunch, going out of town soon, car needing registered before I leave, thus it must get repaired. I'm sorry I just didn't have time to take advantage of your call and expertise. I did take it in and it needed a tune up, and everything else you said it needed. Wow, so glad I had that info going in, thank you, again! She has 124,000+ miles on her, so it was definitely time.
See you on the CorvetteForum!
Burning Brakes
Joined: Jun 2017
Posts: 760
Likes: 242
From: All Over The Place
Hi Bill, thank you so much for the offer to call and help me over the phone. I hear you are the man when it comes to Corvettes and I so appreciate the offer of your time.
I am in a bit of a time crunch, going out of town soon, car needing registered before I leave, thus it must get repaired. I'm sorry I just didn't have time to take advantage of your call and expertise. I did take it in and it needed a tune up, and everything else you said it needed. Wow, so glad I had that info going in, thank you, again! She has 124,000+ miles on her, so it was definitely time.
See you on the CorvetteForum!
I am in a bit of a time crunch, going out of town soon, car needing registered before I leave, thus it must get repaired. I'm sorry I just didn't have time to take advantage of your call and expertise. I did take it in and it needed a tune up, and everything else you said it needed. Wow, so glad I had that info going in, thank you, again! She has 124,000+ miles on her, so it was definitely time.
See you on the CorvetteForum!
There are a few of us here locally, that can lend a hand when needed. KITT and myself for starters. We are a brotherhood/sisterhood, so don't be shy.
Glad you are back up and running!
TC
Racer
Joined: May 2005
Posts: 283
Likes: 16
Please note that you might not be able to take the smog test right away after having your car repaired. Depending on what work was done, there is a possibility that you will have to do a drive cycle as outlined in the link below. Just a heads up so you don't show up at the smog test station and they tell you that your car is not ready to take the test.
The original attached instructions state: 6. Accelerate. Accelerate at 3/4 throttle until 88-96 km/hr (55-60mph). This will perform the same diagnostics as in step 3.
What is not indicated is that in what gear if the car is a manual. I have a 50 state legal turbo modified car, If I accelerate 3/4 throttle I'll either hit the rev limiter or blow through 55-60 like it is not even there.
The reason I bring this up is that my car 68K miles 2004 will not pass smog due to some sensor not set (I'd have to go back and go through the details for which one) I've attempted to do the Drive Cycle but this has not seemed to work for me. Car is legally registered in California as it is, I have a second house in one of 6 counties that do not require smog but would like to figure out though what is going on.
Here is a link to my original post which identifies the readiness sensors that would not set. https://www.corvetteforum.com/forums...ting-help.html
Last edited by Big_George_S; Nov 8, 2019 at 04:06 PM.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
George
If you don't have tuning software, you can purchase a phone APP that interfaces with a Bluetooth dongle that you plug into your ALDL Link that can show you ALL live sensor data and the status of your emissions status flags. Once you determine which emissions flag that is not setting, that will allow you to pin point the issue.
You can also purchase an inexpensive scanner that can read live sensor data AND the emissions data flag status. That is the FIRST step in determining what is NOT Happy!
Bill
If you don't have tuning software, you can purchase a phone APP that interfaces with a Bluetooth dongle that you plug into your ALDL Link that can show you ALL live sensor data and the status of your emissions status flags. Once you determine which emissions flag that is not setting, that will allow you to pin point the issue.
You can also purchase an inexpensive scanner that can read live sensor data AND the emissions data flag status. That is the FIRST step in determining what is NOT Happy!
Bill
Racer
Joined: May 2005
Posts: 283
Likes: 16
Bill,
I've moved your reply over to my original post so we could continue the conversation there.
https://www.corvetteforum.com/forums...ting-help.html
George.
I've moved your reply over to my original post so we could continue the conversation there.
https://www.corvetteforum.com/forums...ting-help.html
George.