LS6/2004 CTS-V Stall and No Start
09-18-2023, 09:30 AM
#1
LS6/2004 CTS-V Stall and No Start Was driving down the road with my family and it just died. Tried to start it again and it sounded like a Harley with major misfiring issues and wouldn't stay started for more than a second or so. Fast forward a week and it still hasn't changed. Towed it back to my garage as I figured it was just a bad ground or something. Here's a list of what I've checked/replaced so far.
1. Crank position sensor - replaced
2. Throttle Position Sensor - replaced (More on this later)
3. Cam position sensor - replaced
4. Checked grounds - specifically the ones at the rear driver side head (which supposedly are the ignition's) but also all that I could find.
5. Checked ignition harnesses for bent pins/dirt - none.
6. Checked fuel pressure at rail - 50 PSI with ignition on and the car not running (obviously).
7. Checked PCM for bent pins/dirt/water damage - none.
8. There are NO codes thrown other than B1004 - which I believe is because I keep on disconnecting the battery to work on the car.
9. Checked fuses - no blown fuses.
10. Cleaned MAF.
11. Checked air filter (replaced 4 months ago) - clean.
Prelim Info: Car has 75k miles. Premium gas all the time. Full synthetic oil changes. No crazy driving pre-breakdown.
Here's what weird about the TPS. I replaced it with a new one but it won't come down to anything lower than around 18% throttle position. That's too high for idle I would think. Looking at old records and from what I remember, throttle position is supposed to sit around 8% at idle. Even with the new TPS, it doesn't SEEM like it wants to go all the way back. Would this cause something as drastic as a sudden stall/no start?
Thanks in advance. I'm going a little crazy - as is my wife - as this is my daily and she has to be my driver everywhere now with her car. LOL.
1. Crank position sensor - replaced
2. Throttle Position Sensor - replaced (More on this later)
3. Cam position sensor - replaced
4. Checked grounds - specifically the ones at the rear driver side head (which supposedly are the ignition's) but also all that I could find.
5. Checked ignition harnesses for bent pins/dirt - none.
6. Checked fuel pressure at rail - 50 PSI with ignition on and the car not running (obviously).
7. Checked PCM for bent pins/dirt/water damage - none.
8. There are NO codes thrown other than B1004 - which I believe is because I keep on disconnecting the battery to work on the car.
9. Checked fuses - no blown fuses.
10. Cleaned MAF.
11. Checked air filter (replaced 4 months ago) - clean.
Prelim Info: Car has 75k miles. Premium gas all the time. Full synthetic oil changes. No crazy driving pre-breakdown.
Here's what weird about the TPS. I replaced it with a new one but it won't come down to anything lower than around 18% throttle position. That's too high for idle I would think. Looking at old records and from what I remember, throttle position is supposed to sit around 8% at idle. Even with the new TPS, it doesn't SEEM like it wants to go all the way back. Would this cause something as drastic as a sudden stall/no start?
Thanks in advance. I'm going a little crazy - as is my wife - as this is my daily and she has to be my driver everywhere now with her car. LOL.
Last edited by Carl_Jones; 09-18-2023 at 09:31 AM. Reason: removed motorcycle video for sound reference as it was too weird.
09-18-2023, 07:57 PM
#2
Post up over at:
https://ls1tech.com/forums/pcm-diagnostics-tuning-7/
This area is for internal engine, might be more help over there
Even try here, someone else could of had similar issue:
https://www.ctsvowners.com/
https://ls1tech.com/forums/pcm-diagnostics-tuning-7/
This area is for internal engine, might be more help over there
Even try here, someone else could of had similar issue:
https://www.ctsvowners.com/
09-23-2023, 07:18 AM
#3
Launching!
Do a search for “TPS relearn ls1tech” and you should find posts that may help. Odd that you have misfires without throwing a corresponding code. If it’s a misfire, I’d be checking plug wires for damage and replacing coils and plugs.
09-24-2023, 08:41 PM
#5
Moderator
Well, you have addresses all the "obvious" possibilities.
I suggest trying yet another crank sensor; make sure its a top quality one. There was just a post here last week about a member getting a new but bad sensor. Same for the TPS.
Or maybe even a bad ECU.
After that I wonder if perhaps the crank's reluctor wheel got loose.
Any of the more experienced tuners/mechanics here have other ideas?
I suggest trying yet another crank sensor; make sure its a top quality one. There was just a post here last week about a member getting a new but bad sensor. Same for the TPS.
Or maybe even a bad ECU.
After that I wonder if perhaps the crank's reluctor wheel got loose.
Any of the more experienced tuners/mechanics here have other ideas?