LS stumbles under acceleration
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LS stumbles under acceleration This might be in the wrong thread but whatever
I have a LS swapped 1973 Camaro which was mainly done by somebody else but it was somewhat half-assed, but it drove and ran completely fine. One example is they just left the PCM in the the engine bay and I hated seeing that eye sore. So, this spring break I took the wiring harness out and finally reworked it. It started and I was happy. That was until I drove it...
The car at first jumped a lot more than I remembered when I put it in drive which was weird but I didn't pay any attention to it. The car began leaking coolant from the steam vent and stumbled during acceleration and sounded like it was backfiring from the exhaust it was really odd. When I would go full throttle it will stumble and then run completely fine, then when I left off it'd stumble a lot. The car idles and revs in park completely fine. So I don't know what to do and I don't have a code reader so that doesn't help either. I know it's not fuel a filter cause the cat has around 500 miles since the swap. The plugs were changed and have spark. I also painted the intake manifold, throttle body, and the stock fuel rails.
Summary: Car is a 5.3 with an LS intake and fuel injectors. Turbo 400 trans. Ran completely fine before I redid the harness. Car stumbles under acceleration and then runs fine and then stumbles. Idles and revs fine. Coolant seems to be leaking from the steam vent and pooling up it sometimes sprays on my windshield. I don't have a code reader so I have no idea. I unplugged the MAF while car was running and it did nothing different.
Thanks for reading and hopefully I can put this car back on the road!!!
-Jesse
I have a LS swapped 1973 Camaro which was mainly done by somebody else but it was somewhat half-assed, but it drove and ran completely fine. One example is they just left the PCM in the the engine bay and I hated seeing that eye sore. So, this spring break I took the wiring harness out and finally reworked it. It started and I was happy. That was until I drove it...
The car at first jumped a lot more than I remembered when I put it in drive which was weird but I didn't pay any attention to it. The car began leaking coolant from the steam vent and stumbled during acceleration and sounded like it was backfiring from the exhaust it was really odd. When I would go full throttle it will stumble and then run completely fine, then when I left off it'd stumble a lot. The car idles and revs in park completely fine. So I don't know what to do and I don't have a code reader so that doesn't help either. I know it's not fuel a filter cause the cat has around 500 miles since the swap. The plugs were changed and have spark. I also painted the intake manifold, throttle body, and the stock fuel rails.
Summary: Car is a 5.3 with an LS intake and fuel injectors. Turbo 400 trans. Ran completely fine before I redid the harness. Car stumbles under acceleration and then runs fine and then stumbles. Idles and revs fine. Coolant seems to be leaking from the steam vent and pooling up it sometimes sprays on my windshield. I don't have a code reader so I have no idea. I unplugged the MAF while car was running and it did nothing different.
Thanks for reading and hopefully I can put this car back on the road!!!
-Jesse
This might be in the wrong thread but whatever I have a LS swapped 1973 Camaro which was mainly done by somebody else but it was somewhat half-assed, but it drove and ran completely fine. One example is they just left the PCM in the the engine bay and I hated seeing that eye sore. So, this spring break I took the wiring harness out and finally reworked it. It started and I was happy. That was until I drove it... The car at first jumped a lot more than I remembered when I put it in drive which was weird but I didn't pay any attention to it. The car began leaking coolant from the steam vent and stumbled during acceleration and sounded like it was backfiring from the exhaust it was really odd. When I would go full throttle it will stumble and then run completely fine, then when I left off it'd stumble a lot. The car idles and revs in park completely fine. So I don't know what to do and I don't have a code reader so that doesn't help either. I know it's not fuel a filter cause the cat has around 500 miles since the swap. The plugs were changed and have spark. I also painted the intake manifold, throttle body, and the stock fuel rails. Summary: Car is a 5.3 with an LS intake and fuel injectors. Turbo 400 trans. Ran completely fine before I redid the harness. Car stumbles under acceleration and then runs fine and then stumbles. Idles and revs fine. Coolant seems to be leaking from the steam vent and pooling up it sometimes sprays on my windshield. I don't have a code reader so I have no idea. I unplugged the MAF while car was running and it did nothing different. Thanks for reading and hopefully I can put this car back on the road!!! -Jesse
After scanning it we realized the o2 sensors weren't reading correctly and after some testing we swapped the o2 harnesses from left to right and that fixed it.
Try swapping your o2 sensor harnesses, you may have crossed them.
This is my best guess without having any further info about what's going on in your tune.
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Teching In
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I recently went through this on my buddies 5.3 swapped c10
After scanning it we realized the o2 sensors weren't reading correctly and after some testing we swapped the o2 harnesses from left to right and that fixed it.
Try swapping your o2 sensor harnesses, you may have crossed them.
This is my best guess without having any further info about what's going on in your tune.
After scanning it we realized the o2 sensors weren't reading correctly and after some testing we swapped the o2 harnesses from left to right and that fixed it.
Try swapping your o2 sensor harnesses, you may have crossed them.
This is my best guess without having any further info about what's going on in your tune.
Thread Starter
Teching In
Joined: Dec 2015
Posts: 23
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