67 Camaro Chokes and Stalls
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Teching In
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67 Camaro Chokes and Stalls 1967 Camaro with 96 [Camaro] LT1 swap (with TH700r)
Just recently purchased; swap was already done.
On cold start, the car fires up and runs fine – well not that fine, but I’ll get to that. After warming up to operating temp, it drives for some time, but then will stall and won’t start until it cools back down – 20-45 minutes later. Any idea what’s going on? That’s the first issue.
The other issue is that while running, if the accelerator is pressed “too hard,” it chokes and sputters as if gas is being cut off. It eventually evens out, but there is no "getting on it." Since purchase, everything from fuel tank up to engine has been replaced – tank, pump, and lines. At wits end on what could be causing it. Any suggestions?
Thanks
Just recently purchased; swap was already done.
On cold start, the car fires up and runs fine – well not that fine, but I’ll get to that. After warming up to operating temp, it drives for some time, but then will stall and won’t start until it cools back down – 20-45 minutes later. Any idea what’s going on? That’s the first issue.
The other issue is that while running, if the accelerator is pressed “too hard,” it chokes and sputters as if gas is being cut off. It eventually evens out, but there is no "getting on it." Since purchase, everything from fuel tank up to engine has been replaced – tank, pump, and lines. At wits end on what could be causing it. Any suggestions?
Thanks
Any idea if there is any tune in the PCM? Do you have a way to look at the engine data to see what's going on, with fuel and timing? Have you checked base engine, oil pressure, compression, leak down, vacuum leaks,etc?
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1967 Camaro with 96 [Camaro] LT1 swap (with TH700r)
On cold start, the car fires up and runs fine – well not that fine, but I’ll get to that. After warming up to operating temp, it drives for some time, but then will stall and won’t start until it cools back down – 20-45 minutes later. Any idea what’s going on? That’s the first issue.Thanks
On cold start, the car fires up and runs fine – well not that fine, but I’ll get to that. After warming up to operating temp, it drives for some time, but then will stall and won’t start until it cools back down – 20-45 minutes later. Any idea what’s going on? That’s the first issue.Thanks
if you replace, use heat sink paste behind it. Typically $1 at auto part stores
as mentioned check fuel pressure first to rule FP issue in/out....especially when stumble occurs
Thread Starter
Teching In
Joined: Jun 2017
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Thread Starter
Teching In
Joined: Jun 2017
Posts: 41
Likes: 1
Another problem is that none of the stock gauges work - speedo/fuel. An external temp gauge was installed that works, and it reads normal.
Oil pressure and compression have not been checked. Vacuum has. I am not familiar with "leak down."
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Teching In
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Ignition control module
Here's a few threads that start out just like yours. Sounds like ***** hit the nail on the head with that one.
http://www.ls1lt1.com/forum/lt1-%7C-...9-bad-icm.html
https://ls1tech.com/forums/lt1-lt4-m...ol-module.html
Here's a few threads that start out just like yours. Sounds like ***** hit the nail on the head with that one.
http://www.ls1lt1.com/forum/lt1-%7C-...9-bad-icm.html
https://ls1tech.com/forums/lt1-lt4-m...ol-module.html
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Teching In
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That's good information about the ICM. I am most familiar with the LS-based engines which does not have a separate ICM.
The ICM will surely be investigated to root out the problem.
I still need to figure out the "choking" symptom when the gas is pressed hard. I may need to get a fuel pressure gauge and also check the fuel injectors.
The ICM will surely be investigated to root out the problem.
I still need to figure out the "choking" symptom when the gas is pressed hard. I may need to get a fuel pressure gauge and also check the fuel injectors.
It's possibly a combination of ICM and Opti acting up. I bet both symptoms are a result of each other. Pull the cap and make sure the sensor is in good shape and that the rotor is tight, then test or replace with a know good one the ICM and see if that fixes your issues.
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That's good information about the ICM. I am most familiar with the LS-based engines which does not have a separate ICM.
The ICM will surely be investigated to root out the problem.
I still need to figure out the "choking" symptom when the gas is pressed hard. I may need to get a fuel pressure gauge and also check the fuel injectors.
The ICM will surely be investigated to root out the problem.
I still need to figure out the "choking" symptom when the gas is pressed hard. I may need to get a fuel pressure gauge and also check the fuel injectors.
I would first check fuel pressure just to rule in/out a fuel problem.
If FP is good I would replace the ICM. AC Delco only. rockauto.com
if still a problem...Opti
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have you check fuel pressure?
what brand ICM did you buy
what brand opti?
did you test coil?
fyi, faulty ICM can corrupt a coil and vice versa...
about the floor it and sputter....is it a stock TB size (48mm) or larger and has the motor been tuned for whatever mods it does have
what brand ICM did you buy
what brand opti?
did you test coil?
fyi, faulty ICM can corrupt a coil and vice versa...
about the floor it and sputter....is it a stock TB size (48mm) or larger and has the motor been tuned for whatever mods it does have
Thread Starter
Teching In
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have you check fuel pressure?
what brand ICM did you buy
what brand opti?
did you test coil?
fyi, faulty ICM can corrupt a coil and vice versa...
about the floor it and sputter....is it a stock TB size (48mm) or larger and has the motor been tuned for whatever mods it does have
what brand ICM did you buy
what brand opti?
did you test coil?
fyi, faulty ICM can corrupt a coil and vice versa...
about the floor it and sputter....is it a stock TB size (48mm) or larger and has the motor been tuned for whatever mods it does have
Haven't swapped Opti.
Unfortunately, the OBD is not working. I don't know if it's because it's not connected or what; still need to figure that out. So, I can see any codes that it may be showing.
I'd start there, being able to read the data and view codes will give you some good direction on where to look and what to test.
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Make sure that the coolant sensor is plugged in, so the computer knows the correct temp. There is a sensor in the cylinder head for the gauge in the dash, and there is a sensor in the front of the water pump for the pcm. If that sensor isn't plugged in, the pcm will leave your car in cold-start mode, and it will be pig rich. It will die after a few minutes, and be very difficult to start.
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Make sure that the coolant sensor is plugged in, so the computer knows the correct temp. There is a sensor in the cylinder head for the gauge in the dash, and there is a sensor in the front of the water pump for the pcm. If that sensor isn't plugged in, the pcm will leave your car in cold-start mode, and it will be pig rich. It will die after a few minutes, and be very difficult to start.