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Discussion Starter #1
the car runs good for about 20 minutes then starts bogging and then dies(CEL is on). RPMS starts going crazy jumping up and down. Sometimes the car starts right up, sometimes it wont. CEL gave crankshaft position senor code, changed it ran good for a day and it went back to bogging(as if it were choking) then dies. A known mechanic said it could probably be the Cat, ordered one from zzp and still same issue. Any help pls.
 

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Whats the exact codes?
Sounds like a dirty throttle body or maf sensor.
 

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Discussion Starter #3
about a 2weeks before this started happening i cleaned the MAF and throttle body with their cleaners. Should i reclean them ?
 

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Whats the exact codes?
Sounds like a dirty throttle body or maf sensor.
Currently i have several codes and they may all be whats causing the issues but,
p0030 bank 1 sensor 1
p0131 bank 1 sensor 1
p0135 bank 1 sensor 1
p0171(the crankshaft code) CHANGED
p0455 evaporative emission leak
p0171 system too lean (bank1)
 

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I almost wonder if you have a fuel injector stuck open
All those have to do with afr
 

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The crank position sensor code is coming back, even after the new sensor? Consider the wiring going to it, I believe they are known for the wiring breaking internally or even the plug having problems with corrosion or losing connection internally. You’d have to catch it doing it and probably lift the car to try moving the wires. Moving the wires when it malfunctions trying to get it to regain connection and verify the bad wire or connector.

Seems like I remember replacing the pig tail for the sensor on a Saturn Vue years back that had this intermittent problem like yours.

The heater circuit for the O2 sensor could be coincidental, won’t really affect the running condition. I would say the evap leak and low voltage at the O2 could indicate a vacuum leak. Make sure you evap lines are not cracked and arent popped off the connections. And if you’re worried about the connectors leaking, you can put something like dielectric grease on the connections to lubricate the O-rings inside the lines.

You may still want to look into a bad fuel injector. You can pull the injectors with the tail out. Once it’s out you can crank the engine and see how they’re spraying. Probably not the safest but it’s fairly standard. And you’re not going to have a ton of fuel coming out anyway. Use your best judgement with that though. You only need to crank the engine for a few seconds to see if the injectors are spraying correctly.
 

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Discussion Starter #8
The crank position sensor code is coming back, even after the new sensor? Consider the wiring going to it, I believe they are known for the wiring breaking internally or even the plug having problems with corrosion or losing connection internally. You’d have to catch it doing it and probably lift the car to try moving the wires. Moving the wires when it malfunctions trying to get it to regain connection and verify the bad wire or connector.

Seems like I remember replacing the pig tail for the sensor on a Saturn Vue years back that had this intermittent problem like yours.

The heater circuit for the O2 sensor could be coincidental, won’t really affect the running condition. I would say the evap leak and low voltage at the O2 could indicate a vacuum leak. Make sure you evap lines are not cracked and arent popped off the connections. And if you’re worried about the connectors leaking, you can put something like dielectric grease on the connections to lubricate the O-rings inside the lines.

You may still want to look into a bad fuel injector. You can pull the injectors with the tail out. Once it’s out you can crank the engine and see how they’re spraying. Probably not the safest but it’s fairly standard. And you’re not going to have a ton of fuel coming out anyway. Use your best judgement with that though. You only need to crank the engine for a few seconds to see if the injectors are spraying correctly.
HEY , forsure ill look into that. I have seen couple videos about the cps and the wiring behind it. THANK YOU !
 

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Yeah I don’t know how the hell it gets messed up. But I have seen it happen. Could be the regular vibration from the engine causes it. I have also seen oil contamination on the wires that causes the plastic coating to become brittle and fall off, then causing the wire to corrode. Have seen the wire’s coating fall off from just the engine heat too and corrode the wires. You’d think they’d make the wiring a little more robust, but they don’t. Even in modern vehicles.
 
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