LS1 sputtering or cutting out..
Thread Starter
Joined: Mar 2003
Posts: 401
Likes: 0
From: Charlotte (Lucia)
Update:
I went to some friends shop and plugged the car up to the tech II and they went through it with the car running. No codes are being thrown (it did show one old instance of a knock sensor, but he said it was probably an error) and everything seems to be running spot on.
I got the electronic fuel pressure gauge installed and went for a 2 hour ride last night. The car cut off on me twice and sputtered while driving a handful of times. The fuel pressure never fluctuate and stayed right at 58lb the whole drive.
I do feel the car has started going rich lately though. I know the A/F gauge is mostly a light show even though we messed with it to read as accurate as possible when tuning the car, but it has been showing rich lately since I have really been looking at it.
Is there a chance I have been all wrong and the car is dumping fuel instead of starving it and causing it to flood out or bog down while driving? I do remember one time it popped pretty loud when I fired it back up when it shut off.
I guess there is a chance bank 1 o2's could be having issues and not showing up on the Tech II? I am at a loss right now.
Worse part is the Blazer went from doing something similar to now it won't crank at all. I actually like that better since it will give me a chance to check for spark and other things as long as it stays consistent.
About a month ago I started going to a new place for fuel that my parents always go too to help cut out the chance of watered down gas.
Not having luck in the vehicle department right now it seems. :\
I went to some friends shop and plugged the car up to the tech II and they went through it with the car running. No codes are being thrown (it did show one old instance of a knock sensor, but he said it was probably an error) and everything seems to be running spot on.
I got the electronic fuel pressure gauge installed and went for a 2 hour ride last night. The car cut off on me twice and sputtered while driving a handful of times. The fuel pressure never fluctuate and stayed right at 58lb the whole drive.
I do feel the car has started going rich lately though. I know the A/F gauge is mostly a light show even though we messed with it to read as accurate as possible when tuning the car, but it has been showing rich lately since I have really been looking at it.
Is there a chance I have been all wrong and the car is dumping fuel instead of starving it and causing it to flood out or bog down while driving? I do remember one time it popped pretty loud when I fired it back up when it shut off.
I guess there is a chance bank 1 o2's could be having issues and not showing up on the Tech II? I am at a loss right now.
Worse part is the Blazer went from doing something similar to now it won't crank at all. I actually like that better since it will give me a chance to check for spark and other things as long as it stays consistent.
About a month ago I started going to a new place for fuel that my parents always go too to help cut out the chance of watered down gas.
Not having luck in the vehicle department right now it seems. :\
Thread Starter
Joined: Mar 2003
Posts: 401
Likes: 0
From: Charlotte (Lucia)
one more thought....two times back in 2003 I had an issue where after I drove to the beach (by chance both times this was the case) the car wouldn't fire it would turn over, but not fire. One time I waited a while and it finally cranked and didn't have the issue again till 5 months later when I drove back down to the beach and exact same case, except this time I replaced some relays suggested and it cranked. The assumption by LS1tech during that time was a crank position sensor, but since it never happened again no matter how long or short the trip I never thought about it again. Any chance that sensor could go without throwing a code?
Staging Lane
Joined: Nov 2005
Posts: 63
Likes: 0
I had a problem with hesitation and stalling, it turned out that a new set of high quality plugs fixed it right up. It was weird too because it did not throw a code at all, but it was definitely not running on all cylinders. Hope this helps 
Thread Starter
Joined: Mar 2003
Posts: 401
Likes: 0
From: Charlotte (Lucia)
The plugs only have 10-13k miles, even TR-6's should go a good bit longer.
I had a break through on the Blazer that reminds me why I hate electrical issues on cars. So I start by making sure I am getting spark, I am, so I start tracing wires from the Distributor to trace grounds. I quickly get to the ground on the Battery and notice it's lose. I try to tighten it and can't, so I pull the ground to find that I stupidly stripped the terminal out (on a nearly new battery
). Now it obviously has to be replaced, but I can't think why if the accessories are working, voltage doesn't drop, and the truck turns over, this would stop it from firing. Go get a new battery and replace it, Blazer fires right up! Again this morning, fires right up. So I got that fixed...
But it got me thinking, the yellow top in the Z is going on 12 years old and has at least 150k miles of use on it over two Fbodies if not more. It still cranks the car even when it stays parked for weeks at a time, still shows strong voltage, but I think I am going to start there, replace the battery and see what happens.
I had a break through on the Blazer that reminds me why I hate electrical issues on cars. So I start by making sure I am getting spark, I am, so I start tracing wires from the Distributor to trace grounds. I quickly get to the ground on the Battery and notice it's lose. I try to tighten it and can't, so I pull the ground to find that I stupidly stripped the terminal out (on a nearly new battery
). Now it obviously has to be replaced, but I can't think why if the accessories are working, voltage doesn't drop, and the truck turns over, this would stop it from firing. Go get a new battery and replace it, Blazer fires right up! Again this morning, fires right up. So I got that fixed...But it got me thinking, the yellow top in the Z is going on 12 years old and has at least 150k miles of use on it over two Fbodies if not more. It still cranks the car even when it stays parked for weeks at a time, still shows strong voltage, but I think I am going to start there, replace the battery and see what happens.
Thread Starter
Joined: Mar 2003
Posts: 401
Likes: 0
From: Charlotte (Lucia)
Update
So while enjoying an evening storm rolling through I started looking around the engine compartment. I check out the Ground strap on the front right side (toward the fuse box) and all looks to be good with that one. While looking around for the other I notice this:
This is on the Pass side, at the back under the AC components and it was resting on the header. Looks like it goes to one of the harnesses that sits on the pass side (I did the hidden wire mod so it is going into the wheel well right now.
Here is a pic of the wires (twisted green and light brown). Any Idea what it goes too? My assumption would have been ABS, but I don't have any ABS lights. But it might not be burnt through yet.
Not sure if it has anything to do with anything, but needs to be fixed anyway and I was curious what it went too. Maybe it's shorting something out.
So while enjoying an evening storm rolling through I started looking around the engine compartment. I check out the Ground strap on the front right side (toward the fuse box) and all looks to be good with that one. While looking around for the other I notice this:
This is on the Pass side, at the back under the AC components and it was resting on the header. Looks like it goes to one of the harnesses that sits on the pass side (I did the hidden wire mod so it is going into the wheel well right now.
Here is a pic of the wires (twisted green and light brown). Any Idea what it goes too? My assumption would have been ABS, but I don't have any ABS lights. But it might not be burnt through yet.
Not sure if it has anything to do with anything, but needs to be fixed anyway and I was curious what it went too. Maybe it's shorting something out.
Registered User
Joined: Sep 2013
Posts: 7
Likes: 0
Hi I'm from Australia and have come across a similiar issue with my car which has been converted to an ls1 setup. It's mechanical auto (t350)
Just wondering what you found was wrong with your car?
Chassis has done 250000klm and as far as I know the fuel pump has to som I've been leaning towards maybe the fuel pump is on its last legs?
If you could let me know what you found it would be a massive help, been trying to troubleshoot for too long now!!
Thanks!
Just wondering what you found was wrong with your car?
Chassis has done 250000klm and as far as I know the fuel pump has to som I've been leaning towards maybe the fuel pump is on its last legs?
If you could let me know what you found it would be a massive help, been trying to troubleshoot for too long now!!
Thanks!
Thread Starter
Joined: Mar 2003
Posts: 401
Likes: 0
From: Charlotte (Lucia)
Hi I'm from Australia and have come across a similiar issue with my car which has been converted to an ls1 setup. It's mechanical auto (t350)
Just wondering what you found was wrong with your car?
Chassis has done 250000klm and as far as I know the fuel pump has to som I've been leaning towards maybe the fuel pump is on its last legs?
If you could let me know what you found it would be a massive help, been trying to troubleshoot for too long now!!
Thanks!
Just wondering what you found was wrong with your car?
Chassis has done 250000klm and as far as I know the fuel pump has to som I've been leaning towards maybe the fuel pump is on its last legs?
If you could let me know what you found it would be a massive help, been trying to troubleshoot for too long now!!
Thanks!
I did fix my issue, I am not sure what you had swapped the LS1 into, but I will describe where my issue was from the point of a 4th gen Camaro.
Looking at this picture you see the group of wiring harness's on the passenger side strut tower.
I had drilled a hole in the tower and ran those harness under the car into the wheel well (very common mod back in the day to hide wires).
I found out that I could lightly shake those wires and make the car stutter and shut down. On command. The wires were very tight.
I ran the wires back to the top, made sure the harness wires were not overly tight and the car hasn't had this issue since. It's been fine for over 2 years now.
I suggest checking what all those harness control and begin checking yours.
Teching In
Joined: Oct 2008
Posts: 4
Likes: 0
From: Centerville, Ga
I'm glad I found this post cuz my TA is doing the exact same thing. My car is now 15 yrs old. I don't think the fuel filter has ever been replaced. So this will be the next investment. Already replaced the O2 sensors and had the transmission serviced.
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Verdad Gallardo Registered User
Joined: Sep 2013
Posts: 7
Likes: 0
ahh yes okay. i have tried to rattle the wiring harness once or twice but didnt come across a fault, i might try again and spend a bit more time and be real thorough. im almost convinced its a wiring issue but hey whos knows
