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Ask GM Tech (Cam) Your Own Question
GM Tech (Cam)
GM Tech (Cam), Chevy Technician
Category: Chevy
Satisfied Customers: 15133
Experience:  GM Grand Master Technician 2007. 14 years experience.
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I have an 07 cobalt. the timing went on the car and i

Customer Question

i have an 07 cobalt. the timing went on the car and i replaced the engine with a correct style engine. with everything plugged where it should be, the car barely starts and when i does it runs like crap and gives me power reduced message. a cel came on for crank position sensor. i noticed the connector was broken. so i replaced the connector and sensor with acdelco products. the fist time i tried to start it it ran great for about two minutes. started to burn rich. i turned the car off, went to restart it. no start. right now i am at a lose
Submitted: 27 days ago.
Category: Chevy
Expert:  AMEDEE replied 27 days ago.

Hello and welcome!

My name is ***** ***** I can assist you with your question.

Expert:  AMEDEE replied 27 days ago.

Would you like the diagram of the timing marks on this engine?

Customer: replied 27 days ago.
no i replaced the engine.
Customer: replied 27 days ago.
i cant figure out why the engine runs rough or wont start
Customer: replied 27 days ago.
hello?
Expert:  AMEDEE replied 27 days ago.

YES, I am here

Expert:  AMEDEE replied 27 days ago.

Are there any codes in the computer?

What is the engine vacuum at when the engine is running?

If it does not start, have you checked for spark?

Does the engine run on starting fluid?

Customer: replied 27 days ago.
i have codes for mass air flow, camshaft sensor, map sensor, throttle position sensor
i have no way of checking the vacuum.
something else i should state is no rpms show on the gauge
Expert:  AMEDEE replied 27 days ago.

Thank you for that information

No RPMS on what gauge? The tach?

Customer: replied 27 days ago.
correct. also on the scanner
Expert:  AMEDEE replied 27 days ago.

Ok, does the engine have spark when cranking?

Have you checked the crank sensor signal and ignition system?

Customer: replied 27 days ago.
i can get the engine to start but it barely runs. it sputters and misses. and burns rich. the crank sensor and connector was just changed with acdelco parts. no change
Expert:  AMEDEE replied 27 days ago.

Have you checked engine compression?

Have you checked for plugged exhaust?

Customer: replied 27 days ago.
exhaust is not plugged. random cel keep coming on.
Expert:  AMEDEE replied 27 days ago.

Ok, so why cant you check engine vacuum?

Customer: replied 27 days ago.
i dont know how. nor do i have a gauge to check vacuum
Expert:  AMEDEE replied 27 days ago.

Ok, sir, I dont think I can help you.

I will leave this open for other experts.

Good luck.

Expert:  Jared D replied 27 days ago.

Hi,

New expert here. Do you still need help with this?

At this point will the engine at least sort of idle?

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