Replaced cam sensor still not right?
#1
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Last week car started getting hard to start. Threw code PO342 which is " Camshaft Position Sensor A Circuit Low Bank 1 or Single Sensor". So I pulled the intake and replaced the cam sensor. I also replaced both knock sensors and harness. Got it all back together today and its still doing the same damn thing. Still throwing the same code. Once it cranks the car idles perfect. When I drive it the car drives great. The problem is when cranking. I don't know what else to do. Any ideas I'm stumped? Thanks.
#3
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#4
TECH Veteran
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Swap the wiring pigtail for the sensor and try again. While it's apart trace the wiring back as far as you can go and make sure nothing looks funky.
Also make sure the grounds are tight on the back side of the drivers cylinder head.
Unplug and reconnect the PCM connectors a few times. You wouldn't believe how many issues I've fixed doing only that in my career as a tech. Connections get corroded over time, unplugging and replugging scrapes the pins and sockets and can fix a poor connection.
Go from there and let us know how it's going.
Also make sure the grounds are tight on the back side of the drivers cylinder head.
Unplug and reconnect the PCM connectors a few times. You wouldn't believe how many issues I've fixed doing only that in my career as a tech. Connections get corroded over time, unplugging and replugging scrapes the pins and sockets and can fix a poor connection.
Go from there and let us know how it's going.
Last edited by 00pooterSS; 09-05-2019 at 05:09 PM.
#5
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Swap the wiring pigtail for the sensor and try again. While it's apart trace the wiring back as far as you can go and make sure nothing looks funky.
Also make sure the grounds are tight on the back side of the drivers cylinder head.
Unplug and reconnect the PCM connectors a few times. You wouldn't believe how many issues I've fixed doing only that in my career as a tech. Connections get corroded over time, unplugging and replugging scrapes the pins and sockets and can fix a poor connection.
Go from there and let us know how it's going.
Also make sure the grounds are tight on the back side of the drivers cylinder head.
Unplug and reconnect the PCM connectors a few times. You wouldn't believe how many issues I've fixed doing only that in my career as a tech. Connections get corroded over time, unplugging and replugging scrapes the pins and sockets and can fix a poor connection.
Go from there and let us know how it's going.
#6
TECH Veteran
iTrader: (40)
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Glad you got it fixed. Crank sensor being funky could cause cam/crank correlation to be off and computer may have had a hard time figuring out which one was the culprit.
Also, every once in a while you come across a code that the factory just got wrong. I had a hyundai come in with a fuel temp sensor code error the other day and the problem was the coolant temp sensor on the engine. We found that out after replacing the fuel temp sensor in the fuel tank.
The problem ended up being that the programming used the coolant temp as a check for the fuel temp, after the car sat over night the temps were both supposed to be ambient temp and if there was a disparity then one of the sensors was wrong. That is correct. What they forgot to do at the factory with the programming was to allow the possibility that the coolant temp sensor could be wrong. For whatever reason they just wrote it to where if there was a difference in temp it threw a code for the fuel temp sensor.
Sorry for writing a book, I'm a tech and I see stuff like this sometimes and it's aggravating. On 07-13 GM trucks, they throw codes for the canister vent valve being bad when in fact it works, but the pressure sensor is stuck. Since the system doesn't see a pressure change, it assumes the vent valve isn't operating. Sometimes they just don't think of every possible scenario, and that's understandable.
Sounds like you've found that type of thing with the cam code on these cars.
Also, every once in a while you come across a code that the factory just got wrong. I had a hyundai come in with a fuel temp sensor code error the other day and the problem was the coolant temp sensor on the engine. We found that out after replacing the fuel temp sensor in the fuel tank.
The problem ended up being that the programming used the coolant temp as a check for the fuel temp, after the car sat over night the temps were both supposed to be ambient temp and if there was a disparity then one of the sensors was wrong. That is correct. What they forgot to do at the factory with the programming was to allow the possibility that the coolant temp sensor could be wrong. For whatever reason they just wrote it to where if there was a difference in temp it threw a code for the fuel temp sensor.
Sorry for writing a book, I'm a tech and I see stuff like this sometimes and it's aggravating. On 07-13 GM trucks, they throw codes for the canister vent valve being bad when in fact it works, but the pressure sensor is stuck. Since the system doesn't see a pressure change, it assumes the vent valve isn't operating. Sometimes they just don't think of every possible scenario, and that's understandable.
Sounds like you've found that type of thing with the cam code on these cars.
#7
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Glad you got it fixed. Crank sensor being funky could cause cam/crank correlation to be off and computer may have had a hard time figuring out which one was the culprit.
Also, every once in a while you come across a code that the factory just got wrong. I had a hyundai come in with a fuel temp sensor code error the other day and the problem was the coolant temp sensor on the engine. We found that out after replacing the fuel temp sensor in the fuel tank.
The problem ended up being that the programming used the coolant temp as a check for the fuel temp, after the car sat over night the temps were both supposed to be ambient temp and if there was a disparity then one of the sensors was wrong. That is correct. What they forgot to do at the factory with the programming was to allow the possibility that the coolant temp sensor could be wrong. For whatever reason they just wrote it to where if there was a difference in temp it threw a code for the fuel temp sensor.
Sorry for writing a book, I'm a tech and I see stuff like this sometimes and it's aggravating. On 07-13 GM trucks, they throw codes for the canister vent valve being bad when in fact it works, but the pressure sensor is stuck. Since the system doesn't see a pressure change, it assumes the vent valve isn't operating. Sometimes they just don't think of every possible scenario, and that's understandable.
Sounds like you've found that type of thing with the cam code on these cars.
Also, every once in a while you come across a code that the factory just got wrong. I had a hyundai come in with a fuel temp sensor code error the other day and the problem was the coolant temp sensor on the engine. We found that out after replacing the fuel temp sensor in the fuel tank.
The problem ended up being that the programming used the coolant temp as a check for the fuel temp, after the car sat over night the temps were both supposed to be ambient temp and if there was a disparity then one of the sensors was wrong. That is correct. What they forgot to do at the factory with the programming was to allow the possibility that the coolant temp sensor could be wrong. For whatever reason they just wrote it to where if there was a difference in temp it threw a code for the fuel temp sensor.
Sorry for writing a book, I'm a tech and I see stuff like this sometimes and it's aggravating. On 07-13 GM trucks, they throw codes for the canister vent valve being bad when in fact it works, but the pressure sensor is stuck. Since the system doesn't see a pressure change, it assumes the vent valve isn't operating. Sometimes they just don't think of every possible scenario, and that's understandable.
Sounds like you've found that type of thing with the cam code on these cars.
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#9
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Glad you got it fixed! Not sure if you've done this, but you may need to also perform a crank and cam position relearn procedure to synchronize. Sounds like you're good to go though. I actually had a similar issue but my motor wouldn't fire until I cycled the crank 3 times. I started out replacing crank sensor as that's about 100x easier to replace than the cam pos sensor. It was on my way to get the crank relearn I saw my tac needle drop to 0. Bingo...cam pos sensor. Here I am today as I just swapped out the sensor and have the intake manifold back on the car. Time to torque it down to spec and cross the fingers lol
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NoSmokies (09-12-2019)
#11
Teching In
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Piggy backing off the OP here but I was in a similar situation as stated above. After I replaced the cam sensor the car fired up just fine. I let the motor idle a few minutes, checked for vacuum leaks, anything out of place and seemed okay so I drove the car around the block. About 5 minutes into a normal drive the tac needle again dropped to 0 and the random misfire came back.
This usually always happens within the first 5 minutes of the cruise and lasts only a minute or two until the needle finds it's place again and the car drives normally. If I were to do a quick pull at this point the engine will shut off at high RPM. While I had the intake manifold off I inspected that 6" to 8" of exposed wiring to check for breaks or corrosion and it looked okay.
My thought at this point is an ECU issue. The motor is stock besides a lid and HP tune done at reputable race shop.
This usually always happens within the first 5 minutes of the cruise and lasts only a minute or two until the needle finds it's place again and the car drives normally. If I were to do a quick pull at this point the engine will shut off at high RPM. While I had the intake manifold off I inspected that 6" to 8" of exposed wiring to check for breaks or corrosion and it looked okay.
My thought at this point is an ECU issue. The motor is stock besides a lid and HP tune done at reputable race shop.