Evap vent solenoid testing
#51
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Next question... Is it a 2005 Trailblazer or a regular Blazer. Different engines. Looks like you may be Canadian - refer to Kilometers. IMHO Car diagnostic Pro is the best bluetooth app and the BAFX is the best Bluetooth adapter for your vehicle. Not sure why you are having any troubles - maybe the setup or how you are trying to run it... never saw any problems with anything but 1996-97 Blazers.
Last edited by LesMyer; 10-19-2022 at 12:41 PM.
#53
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You have B1S1 and B2S1 as your pre-catalytic converter O2 sensors (two Banks, right and left). The third, a post-catalytic converter O2 sensor is B1S2. B=bank# S=sensor#
What year is your Blazer?
George, I'm not trying to take over. Just making sure he is not trying to use Car Gauge Pro or Car Diagnostic Pro on a 1996 or 1997 Blazer. It doesn't work for the Enhanced GM PIDs for those two years with the older PCM. However it does work for the SAE Generic PIDs. I don't see where he stated his year.
What year is your Blazer?
George, I'm not trying to take over. Just making sure he is not trying to use Car Gauge Pro or Car Diagnostic Pro on a 1996 or 1997 Blazer. It doesn't work for the Enhanced GM PIDs for those two years with the older PCM. However it does work for the SAE Generic PIDs. I don't see where he stated his year.
Appreciate the help on the scanners. Ya, the post cat sensor is either B1S2 or B1S3 depending on the year. OP: if that sensor is working right it will be a straight voltage line between 0.5 - 0.7v unless the cat is still cold or failed.
George
#54
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The OP originally thought he had a vacuum leak and did not understand how the evap system works. I was trying to help him learn about these two things and help him discover that there is no vacuum leak. He was making assumptions without any data so I was teaching him how to analyze his truck to draw conclusions. Then he seemed to want to learn how to use his scanner and check his sensors so we have been doing that. Along the way he mentioned misfires and fuel mileage and an erratic ECT sensor hence the focus on fuel trims the O2 sensors and a cross check of the ECT reading with Torque. next would have been misfire counters and sensor data during the flashing CEL. I have been wandering around with him to work with his thought process and help him learn how to diagnose and work on his truck. He also mentioned that he wants to go slow and that all of this is new to him. Had he said I have problem X, how do we fix it, this would have been more focused but we are also here to teach people how to be better mechanics and problem solvers.
Last edited by GeorgeLG; 10-19-2022 at 02:36 PM.
#55
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Yes it's a 2005 Blazer Les. I appreciate both of you and George's help and yes I'm Canadian. I have alot of American friends. Anyhow I can't get torque lite to work with my BAFX adapter so what do you suggest I check next George ? I'm not sure how or if you wanted me to check the cat O2 ?
Thanks
Jason
Thanks
Jason
#56
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All right then
The OP originally thought he had a vacuum leak and did not understand how the evap system works. I was trying to help him learn about these two things and help him discover that there is no vacuum leak. He was making assumptions without any data so I was teaching him how to analyze his truck to draw conclusions. Then he seemed to want to learn how to use his scanner and check his sensors so we have been doing that. Along the way he mentioned misfires and fuel mileage and an erratic ECT sensor hence the focus on fuel trims the O2 sensors and a cross check of the ECT reading with Torque. next would have been misfire counters and sensor data during the flashing CEL. I have been wandering around with him to work with his thought process and help him learn how to diagnose and work on his truck. He also mentioned that he wants to go slow and that all of this is new to him. Had he said I have problem X, how do we fix it, this would have been more focused but we are also here to teach people how to be better mechanics and problem solvers.
The OP originally thought he had a vacuum leak and did not understand how the evap system works. I was trying to help him learn about these two things and help him discover that there is no vacuum leak. He was making assumptions without any data so I was teaching him how to analyze his truck to draw conclusions. Then he seemed to want to learn how to use his scanner and check his sensors so we have been doing that. Along the way he mentioned misfires and fuel mileage and an erratic ECT sensor hence the focus on fuel trims the O2 sensors and a cross check of the ECT reading with Torque. next would have been misfire counters and sensor data during the flashing CEL. I have been wandering around with him to work with his thought process and help him learn how to diagnose and work on his truck. He also mentioned that he wants to go slow and that all of this is new to him. Had he said I have problem X, how do we fix it, this would have been more focused but we are also here to teach people how to be better mechanics and problem solvers.
Last edited by LesMyer; 10-19-2022 at 03:33 PM.
#57
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I only get a flashing CEL when I do over 80km / 50mph. So I try not to go on the hwy but sometimes when I do go on the hwy it doesn't flash at all. My gas mileage is horrible I get 240km / 150miles to a full tank of gas. The truck run as if I disconnected the vacuum advance on engine with a carburetor.
#58
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The rear O2 sensor primarily tells us the health of the CAT, we can forget about that for now.
Les knows more about all of the BT scanner apps than I do so I cant guide you on torque lite.
I wanted to see your two pre cat O2 sensors primarily which we did and they look good. I also want to use torque to confirm that wonky ECT reading because that can affect fuel delivery. I also have been waiting for you to get comfortable with this scanner set up so that we can add misfire counters to see if its all or some cylinders and to see if any of the sensors go wacky when the CEL light flashes. How does it run exactly, what does a carbureted engine with poor vacuum advance mean to you?
Do you have a recent compression test?
Once we have the cylinders that are misfiring we need to look at some plugs.
George
Les knows more about all of the BT scanner apps than I do so I cant guide you on torque lite.
I wanted to see your two pre cat O2 sensors primarily which we did and they look good. I also want to use torque to confirm that wonky ECT reading because that can affect fuel delivery. I also have been waiting for you to get comfortable with this scanner set up so that we can add misfire counters to see if its all or some cylinders and to see if any of the sensors go wacky when the CEL light flashes. How does it run exactly, what does a carbureted engine with poor vacuum advance mean to you?
Do you have a recent compression test?
Once we have the cylinders that are misfiring we need to look at some plugs.
George
#59
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Flashing CEL & ECT - #7. He has also had a MAF code.
Last edited by GeorgeLG; 10-19-2022 at 04:26 PM.