Tech 2 Diagnostic Help C6 Dies after 50 min running
08-21-2017, 06:20 PM
#1
Safety Car
Thread Starter
Tech 2 Diagnostic Help C6 Dies after 50 min running
I have a 2005 C6 that runs rough and dies after 50 min of idling.
Just got a Tech 2 and ran a snapshot. Triggered on a any code.
It throws a P0203.
BUT looking through the snapshot, the EVAP Purge Solenoid Com goes from 15% to 0% the instant the engine starts to run rough and throws the code.
Is this due to it throwing the code or is it because it is reading 0% causing it to run rough. Research so far says this valve failing will cause a super lean condition and run rough.
Any thoughs?
Just got a Tech 2 and ran a snapshot. Triggered on a any code.
It throws a P0203.
BUT looking through the snapshot, the EVAP Purge Solenoid Com goes from 15% to 0% the instant the engine starts to run rough and throws the code.
Is this due to it throwing the code or is it because it is reading 0% causing it to run rough. Research so far says this valve failing will cause a super lean condition and run rough.
Any thoughs?
08-21-2017, 06:28 PM
#2
Safety Car
Thread Starter
Continuing to look through the snapshot.
The CMP Sensor always reads 1012 RPM no matter what. Running or not.
How is that possible?
Obviously this is most likely the problem but has anyone seen anything like this??
I may start a separate thread to troll for some answers.
Any thoughts?
The CMP Sensor always reads 1012 RPM no matter what. Running or not.
How is that possible?
Obviously this is most likely the problem but has anyone seen anything like this??
I may start a separate thread to troll for some answers.
Any thoughts?
08-22-2017, 08:11 AM
#3
Burning Brakes
There's another thread here on P0203 that seems to point to electrical issues around the injectors. Given that, plus your sensor strangeness, I'd be starting with close inspection of the wiring, especially the connectors into the ECM.
The following users liked this post:
TedG (08-22-2017)
08-22-2017, 10:26 AM
#4
Safety Car
Thread Starter
There's another thread here on P0203 that seems to point to electrical issues around the injectors. Given that, plus your sensor strangeness, I'd be starting with close inspection of the wiring, especially the connectors into the ECM.
I will take the advice of the guy helping him.
Thanks.
08-22-2017, 02:34 PM
#5
Safety Car
Thread Starter
TTT update.
Cleared all the codes yesterday with the Tech 2 to make sure I have a clean slate.
Ran the car to get some gas then went home, hooked up the Tech 2 and did a snapshot that would trigger on a thrown code.
It died, but never triggered a code so I got no snapshot. Started it up and it ran flawlessly for 30 seconds, then died. Again no code, no Traction Control Service. Just dead. Tried to start it a few times and it cranked efffortlessy but wouldn't start. Now it needs to cool before it starts. I may have to manually trigger it.
Cleared all the codes yesterday with the Tech 2 to make sure I have a clean slate.
Ran the car to get some gas then went home, hooked up the Tech 2 and did a snapshot that would trigger on a thrown code.
It died, but never triggered a code so I got no snapshot. Started it up and it ran flawlessly for 30 seconds, then died. Again no code, no Traction Control Service. Just dead. Tried to start it a few times and it cranked efffortlessy but wouldn't start. Now it needs to cool before it starts. I may have to manually trigger it.
08-22-2017, 03:43 PM
#6
Burning Brakes
TTT update.
Cleared all the codes yesterday with the Tech 2 to make sure I have a clean slate.
Ran the car to get some gas then went home, hooked up the Tech 2 and did a snapshot that would trigger on a thrown code.
It died, but never triggered a code so I got no snapshot. Started it up and it ran flawlessly for 30 seconds, then died. Again no code, no Traction Control Service. Just dead. Tried to start it a few times and it cranked efffortlessy but wouldn't start. Now it needs to cool before it starts. I may have to manually trigger it.
Cleared all the codes yesterday with the Tech 2 to make sure I have a clean slate.
Ran the car to get some gas then went home, hooked up the Tech 2 and did a snapshot that would trigger on a thrown code.
It died, but never triggered a code so I got no snapshot. Started it up and it ran flawlessly for 30 seconds, then died. Again no code, no Traction Control Service. Just dead. Tried to start it a few times and it cranked efffortlessy but wouldn't start. Now it needs to cool before it starts. I may have to manually trigger it.
You are creating a negative pressure in the gas tank, and that is fighting the fuel pump's ability to pull fuel into the engine, thus starving the engine of fuel.
Then as it sits, the pressure will eventually equalize, and the car is able to start again.
Pull the Purge solenoid vac line from the engine and plug it, then remove the gas cap and run the car. See if the car stays running longer.
I don't think the false PID of the cam sensor is killing your engine. If the sensor were bad, the engine wouldn't start, as it wouldn't know when to fire the injectors or coil packs.
Try it and let us know. I might be way off here, but I think its worth a try. Its hard to diagnose an engine problem over the internet....
08-22-2017, 04:27 PM
#7
Safety Car
Thread Starter
If you have a stuck open purge solenoid and a clogged or stuck closed vent solenoid, it will make the engine run rough and then die.
You are creating a negative pressure in the gas tank, and that is fighting the fuel pump's ability to pull fuel into the engine, thus starving the engine of fuel.
Then as it sits, the pressure will eventually equalize, and the car is able to start again.
Pull the Purge solenoid vac line from the engine and plug it, then remove the gas cap and run the car. See if the car stays running longer.
I don't think the false PID of the cam sensor is killing your engine. If the sensor were bad, the engine wouldn't start, as it wouldn't know when to fire the injectors or coil packs.
Try it and let us know. I might be way off here, but I think its worth a try. Its hard to diagnose an engine problem over the internet....
You are creating a negative pressure in the gas tank, and that is fighting the fuel pump's ability to pull fuel into the engine, thus starving the engine of fuel.
Then as it sits, the pressure will eventually equalize, and the car is able to start again.
Pull the Purge solenoid vac line from the engine and plug it, then remove the gas cap and run the car. See if the car stays running longer.
I don't think the false PID of the cam sensor is killing your engine. If the sensor were bad, the engine wouldn't start, as it wouldn't know when to fire the injectors or coil packs.
Try it and let us know. I might be way off here, but I think its worth a try. Its hard to diagnose an engine problem over the internet....
In the snapshot I took, 2 frames before it threw a code it showed EVAP Purge Solenoid Com at 15% then it went to 0 and then it threw the p0203 code, ran rough and died.
As stated in the orig post.
Last edited by TedG; 08-22-2017 at 04:28 PM.
08-23-2017, 05:22 PM
#8
Safety Car
Thread Starter
If you have a stuck open purge solenoid and a clogged or stuck closed vent solenoid, it will make the engine run rough and then die.
You are creating a negative pressure in the gas tank, and that is fighting the fuel pump's ability to pull fuel into the engine, thus starving the engine of fuel.
Then as it sits, the pressure will eventually equalize, and the car is able to start again.
Pull the Purge solenoid vac line from the engine and plug it, then remove the gas cap and run the car. See if the car stays running longer.
I don't think the false PID of the cam sensor is killing your engine. If the sensor were bad, the engine wouldn't start, as it wouldn't know when to fire the injectors or coil packs.
Try it and let us know. I might be way off here, but I think its worth a try. Its hard to diagnose an engine problem over the internet....
You are creating a negative pressure in the gas tank, and that is fighting the fuel pump's ability to pull fuel into the engine, thus starving the engine of fuel.
Then as it sits, the pressure will eventually equalize, and the car is able to start again.
Pull the Purge solenoid vac line from the engine and plug it, then remove the gas cap and run the car. See if the car stays running longer.
I don't think the false PID of the cam sensor is killing your engine. If the sensor were bad, the engine wouldn't start, as it wouldn't know when to fire the injectors or coil packs.
Try it and let us know. I might be way off here, but I think its worth a try. Its hard to diagnose an engine problem over the internet....
08-25-2017, 04:24 PM
#9
Instructor
3 sys make any car runs ...no matter a model T or a Lamborghini Aventador...spark,compression mechanical and air /fuel ctrl....and they all have to
happen at the correct time ..... any real mechanic look at that yet ?? ..or just arm chair Monday morning quarter back with no related reason by listening to your symptoms and throwing guesses because it happen in the past .....
happen at the correct time ..... any real mechanic look at that yet ?? ..or just arm chair Monday morning quarter back with no related reason by listening to your symptoms and throwing guesses because it happen in the past .....
08-25-2017, 07:02 PM
#10
Safety Car
Thread Starter
3 sys make any car runs ...no matter a model T or a Lamborghini Aventador...spark,compression mechanical and air /fuel ctrl....and they all have to
happen at the correct time ..... any real mechanic look at that yet ?? ..or just arm chair Monday morning quarter back with no related reason by listening to your symptoms and throwing guesses because it happen in the past .....
happen at the correct time ..... any real mechanic look at that yet ?? ..or just arm chair Monday morning quarter back with no related reason by listening to your symptoms and throwing guesses because it happen in the past .....
Yes, you are correct in saying the there are those systems. But is it a bit more complicated than it used to be.
The problem here is the dealer will use the same tool and charge big money to do so. And my dealer is mostly incompetent, no real experts. If the Tech2 doesn't lead them to the answer, they don't know.
The reason for posting is to find an answer. There are hundreds of people here that have experienced many problems. Many a person has been helped.
Yes, I just got the tool and am learning to use it.
I used to be a professional mechanic when I was younger. Now I write code for embedded systems and design the electronics. Kind of a gear head geek.
So I would like to fix it, learn how to use this new tool and the next time something wrong happens to someone or myself, I might be able to help that someone or myself.
08-26-2017, 02:03 AM
#12
Instructor
if a vehicle gas contents in here the south using 10% ehanol has more than 10 percent ...car runs with misfire ..or some1 accidentally put diesel in ..but guess what -->no codes ... it take classes and entry level of qualification knowing the ability and limitation of every tools such as 5 gas analyzer ,scope ,infra,scan tool ..etc ..but further more ..it take the person knowing when to use the which tool to narrow down the cause ...scan tool is not god ...if it is ...every 1 I use I keep up my training how to use it ... not by guessing
08-26-2017, 02:59 AM
#13
Instructor
???
If you have a stuck open purge solenoid and a clogged or stuck closed vent solenoid, it will make the engine run rough and then die.
You are creating a negative pressure in the gas tank, and that is fighting the fuel pump's ability to pull fuel into the engine, thus starving the engine of fuel.
Then as it sits, the pressure will eventually equalize, and the car is able to start again.
Pull the Purge solenoid vac line from the engine and plug it, then remove the gas cap and run the car. See if the car stays running longer.
I don't think the false PID of the cam sensor is killing your engine. If the sensor were bad, the engine wouldn't start, as it wouldn't know when to fire the injectors or coil packs.
Try it and let us know. I might be way off here, but I think its worth a try. Its hard to diagnose an engine problem over the internet....
You are creating a negative pressure in the gas tank, and that is fighting the fuel pump's ability to pull fuel into the engine, thus starving the engine of fuel.
Then as it sits, the pressure will eventually equalize, and the car is able to start again.
Pull the Purge solenoid vac line from the engine and plug it, then remove the gas cap and run the car. See if the car stays running longer.
I don't think the false PID of the cam sensor is killing your engine. If the sensor were bad, the engine wouldn't start, as it wouldn't know when to fire the injectors or coil packs.
Try it and let us know. I might be way off here, but I think its worth a try. Its hard to diagnose an engine problem over the internet....
08-26-2017, 11:47 AM
#14
Instructor
[QUOTE=TedG;1595440691]TTT,
Also looking through the snapshot, I notice that 12 seconds before it threw a code the Loop Status went from Closed to Open.
Any thoughts?[/QUOTE
Last time I check on TEch2 ...we paid around $5k plus license & subscription for programming each year ...but tech2 is not capable of recording live data parameters during before or after a code set .... snap shot only show 7 sec after a code are set ....so ....7 sec is a long time before data change ...why not looking at mode 6 on test value on OBD2?.... all hell can break lose after 7 seconds not even close to accurate ....u don't even know this is an idling issue or engine performance cause ....if it stall everytime after cold start ...does it stay running if you rev up the engine ???....that determine if it is an idling issue or not ...before you went to the deep end and wandering into evap...just in case experience count ... current subscription of GM site , complete auto info sub access such as motor logic,all data with factory schematic ..probably a scope and an after market record capability not tech2 but such as snap on verus ,autel is basically whats all of above a tech select to nail a stall
issue ......by just base on past experiences happened on 1 condition that apply to others without understanding the nature of the objective..I bet the differences....
Also looking through the snapshot, I notice that 12 seconds before it threw a code the Loop Status went from Closed to Open.
Any thoughts?[/QUOTE
Last time I check on TEch2 ...we paid around $5k plus license & subscription for programming each year ...but tech2 is not capable of recording live data parameters during before or after a code set .... snap shot only show 7 sec after a code are set ....so ....7 sec is a long time before data change ...why not looking at mode 6 on test value on OBD2?.... all hell can break lose after 7 seconds not even close to accurate ....u don't even know this is an idling issue or engine performance cause ....if it stall everytime after cold start ...does it stay running if you rev up the engine ???....that determine if it is an idling issue or not ...before you went to the deep end and wandering into evap...just in case experience count ... current subscription of GM site , complete auto info sub access such as motor logic,all data with factory schematic ..probably a scope and an after market record capability not tech2 but such as snap on verus ,autel is basically whats all of above a tech select to nail a stall
issue ......by just base on past experiences happened on 1 condition that apply to others without understanding the nature of the objective..I bet the differences....
08-26-2017, 11:58 AM
#15
TTT update.
Cleared all the codes yesterday with the Tech 2 to make sure I have a clean slate.
Ran the car to get some gas then went home, hooked up the Tech 2 and did a snapshot that would trigger on a thrown code.
It died, but never triggered a code so I got no snapshot. Started it up and it ran flawlessly for 30 seconds, then died. Again no code, no Traction Control Service. Just dead. Tried to start it a few times and it cranked efffortlessy but wouldn't start. Now it needs to cool before it starts. I may have to manually trigger it.
Cleared all the codes yesterday with the Tech 2 to make sure I have a clean slate.
Ran the car to get some gas then went home, hooked up the Tech 2 and did a snapshot that would trigger on a thrown code.
It died, but never triggered a code so I got no snapshot. Started it up and it ran flawlessly for 30 seconds, then died. Again no code, no Traction Control Service. Just dead. Tried to start it a few times and it cranked efffortlessy but wouldn't start. Now it needs to cool before it starts. I may have to manually trigger it.
08-26-2017, 12:22 PM
#16
Safety Car
Thread Starter
All reference voltages never waiver.
I have put a fuel pressure gauge on it and there is 58 even when it wont start.
The CKP looks fairly accurate, the CMP rpm is static (which I have stated in another thread).
Remember half the time this doesn't even throw a code.
The next step is to see if the injectors are firing when it dies.
Ted
08-26-2017, 12:25 PM
#17
Safety Car
Thread Starter
[QUOTE=kcbc;1595444126]
The snapshot is 1:32 before the code was thrown and 2:10 after,
each frame was taken .375 seconds apart.
If you step on the throttle when it starts to die it will try to rev but still dies you can not keep it running. When it is not dying it runs great. Cold start, runs great. Cool day, runs longer. Only seems to die when idling or in stop and go situations. Never died unless it got hot first.
1/4th of the time it won't even throw a code. I can still drive it 30 - 40 miles maybe more if it is cool. I don't want to get stranded.
I have found most of the grounds but I need to find G105 that is the ECM ground. I found G107.
Every connection I have checked is clean, pristine and dry. There is absolutely no corrosion on any connector anywhere. Reno is a very dry climate.
TTT,
Also looking through the snapshot, I notice that 12 seconds before it threw a code the Loop Status went from Closed to Open.
Any thoughts?[/QUOTE
Last time I check on TEch2 ...we paid around $5k plus license & subscription for programming each year ...but tech2 is not capable of recording live data parameters during before or after a code set .... snap shot only show 7 sec after a code are set ....so ....7 sec is a long time before data change ...why not looking at mode 6 on test value on OBD2?.... all hell can break lose after 7 seconds not even close to accurate ....u don't even know this is an idling issue or engine performance cause ....if it stall everytime after cold start ...does it stay running if you rev up the engine ???....that determine if it is an idling issue or not ...before you went to the deep end and wandering into evap...just in case experience count ... current subscription of GM site , complete auto info sub access such as motor logic,all data with factory schematic ..probably a scope and an after market record capability not tech2 but such as snap on verus ,autel is basically whats all of above a tech select to nail a stall
issue ......by just base on past experiences happened on 1 condition that apply to others without understanding the nature of the objective..I bet the differences....
Also looking through the snapshot, I notice that 12 seconds before it threw a code the Loop Status went from Closed to Open.
Any thoughts?[/QUOTE
Last time I check on TEch2 ...we paid around $5k plus license & subscription for programming each year ...but tech2 is not capable of recording live data parameters during before or after a code set .... snap shot only show 7 sec after a code are set ....so ....7 sec is a long time before data change ...why not looking at mode 6 on test value on OBD2?.... all hell can break lose after 7 seconds not even close to accurate ....u don't even know this is an idling issue or engine performance cause ....if it stall everytime after cold start ...does it stay running if you rev up the engine ???....that determine if it is an idling issue or not ...before you went to the deep end and wandering into evap...just in case experience count ... current subscription of GM site , complete auto info sub access such as motor logic,all data with factory schematic ..probably a scope and an after market record capability not tech2 but such as snap on verus ,autel is basically whats all of above a tech select to nail a stall
issue ......by just base on past experiences happened on 1 condition that apply to others without understanding the nature of the objective..I bet the differences....
each frame was taken .375 seconds apart.
If you step on the throttle when it starts to die it will try to rev but still dies you can not keep it running. When it is not dying it runs great. Cold start, runs great. Cool day, runs longer. Only seems to die when idling or in stop and go situations. Never died unless it got hot first.
1/4th of the time it won't even throw a code. I can still drive it 30 - 40 miles maybe more if it is cool. I don't want to get stranded.
I have found most of the grounds but I need to find G105 that is the ECM ground. I found G107.
Every connection I have checked is clean, pristine and dry. There is absolutely no corrosion on any connector anywhere. Reno is a very dry climate.
Last edited by TedG; 08-26-2017 at 12:41 PM.
08-27-2017, 12:44 AM
#19
Instructor
[QUOTE=TedG;1595444320]
We use all data and motor logic in our shop .....let me know what else you need to find location...
The snapshot is 1:32 before the code was thrown and 2:10 after,
each frame was taken .375 seconds apart.
If you step on the throttle when it starts to die it will try to rev but still dies you can not keep it running. When it is not dying it runs great. Cold start, runs great. Cool day, runs longer. Only seems to die when idling or in stop and go situations. Never died unless it got hot first.
1/4th of the time it won't even throw a code. I can still drive it 30 - 40 miles maybe more if it is cool. I don't want to get stranded.
I have found most of the grounds but I need to find G105 that is the ECM ground. I found G107.
Every connection I have checked is clean, pristine and dry. There is absolutely no corrosion on any connector anywhere. Reno is a very dry climate.
each frame was taken .375 seconds apart.
If you step on the throttle when it starts to die it will try to rev but still dies you can not keep it running. When it is not dying it runs great. Cold start, runs great. Cool day, runs longer. Only seems to die when idling or in stop and go situations. Never died unless it got hot first.
1/4th of the time it won't even throw a code. I can still drive it 30 - 40 miles maybe more if it is cool. I don't want to get stranded.
I have found most of the grounds but I need to find G105 that is the ECM ground. I found G107.
Every connection I have checked is clean, pristine and dry. There is absolutely no corrosion on any connector anywhere. Reno is a very dry climate.
08-27-2017, 12:51 AM
#20
Instructor
snap shot
[QUOTE=TedG;1595444320]
understand how a code is generate by the definition on all car after 96' OBD2....it has the TID(test id) and CID(component id) and it will show on mode 6 on obd2 mode its own test max & min value.... but it also show you when a component about to go out how far it get close to the limit even ur car show no symptoms......when you find out which parameter id show close limit value then you can zoom in your cpt and sys....tech 2 only good for programming and bidirectional value...it wont give color graph recording and that what I'll do when I need to chase ghost... I like my snap on verus which it can set recording on live data on all my parameters and play it back
after it stop acting up....
The snapshot is 1:32 before the code was thrown and 2:10 after,
each frame was taken .375 seconds apart.
If you step on the throttle when it starts to die it will try to rev but still dies you can not keep it running. When it is not dying it runs great. Cold start, runs great. Cool day, runs longer. Only seems to die when idling or in stop and go situations. Never died unless it got hot first.
1/4th of the time it won't even throw a code. I can still drive it 30 - 40 miles maybe more if it is cool. I don't want to get stranded.
I have found most of the grounds but I need to find G105 that is the ECM ground. I found G107.
Every connection I have checked is clean, pristine and dry. There is absolutely no corrosion on any connector anywhere. Reno is a very dry climate.
each frame was taken .375 seconds apart.
If you step on the throttle when it starts to die it will try to rev but still dies you can not keep it running. When it is not dying it runs great. Cold start, runs great. Cool day, runs longer. Only seems to die when idling or in stop and go situations. Never died unless it got hot first.
1/4th of the time it won't even throw a code. I can still drive it 30 - 40 miles maybe more if it is cool. I don't want to get stranded.
I have found most of the grounds but I need to find G105 that is the ECM ground. I found G107.
Every connection I have checked is clean, pristine and dry. There is absolutely no corrosion on any connector anywhere. Reno is a very dry climate.
after it stop acting up....