How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask FixItMan Your Own Question
FixItMan
FixItMan, Master Technician
Category: Car
Satisfied Customers: 17462
Experience:  AA DEGREE AUTOMOTIVE/DIESEL TECH
1627031
Type Your Car Question Here...
FixItMan is online now
A new question is answered every 9 seconds

checy 2500: my 07 duramax started smoking and knocking while

This answer was rated:

my 07 duramax started smoking and knocking while driving pulling our camper put reader on it said crank sensor out of range is this the problem
Hi,how are you?The noise and smoking is most likely not going to be caused from the crank sensor.How does the oil look and was it full?
Customer: replied 5 years ago.
yes oil was changed before we left for vacation
Ok,what this is consistent with is the vehicle timing has jumped,this would also throw the crankshaft timing out of range which would give you the code that you are getting.This would happen do to a timing guide or timing chain tensioner failure.The timing cover would need to be removed and the vehicle should be checked out right away.
Customer: replied 5 years ago.
doubt that i am a deisel mechanic just have not worked on many duramax engines just drive them truck runs way to good to be jumped time has to be some thing was driving in very heavy rain for about 200 miles
Customer: replied 5 years ago.
,doubt that i am a deisel mechanic just have not worked on many duramax engines just drive them truck runs way to good to be jumped time has to be some thing was driving in very heavy rain for about 200 miles
Ok,as a diesel mechanic,you know that the knocking and smoking is not a good thing and is consistent with a mechanical failure and not a electrical failure,i would at minimum suggest checking the compression on each cylinder.
Customer: replied 5 years ago.
the knock is only at a higher rpm quite as a kitten idling it goes away once load leaves only smokes will excelerating

Ok,i will opt out and open the question back up,don't respond to the question or it will lock me back in,someone will be with you shortly,thank you.

Customer: replied 5 years ago.
Do you know when one will be available?
Hello, and thank you for letting us help you with your automotive question. I would like to get a little more information from you. What was the computer code you received? What color is the smoke? Is it the same whether the engine is hot or cold?
Customer: replied 5 years ago.
The code was the crank shaft sensor is out of range. The smoke was both white and black but was mostly black. This was while the engine was hot but is the same whether it is hot or cold. Once I cleared the codes it hasn't sent them back.
Okay. Thank you for the reply. The code for the crank sensor may have been a false code. It may be due to the way the vehicle is running. I would start by looking into a bad fuel injector. A bad or leaking injector will cause too much fuel to be dumped into the engine and will cause this smoke and will cause the engine to misfire and/or knock. I would recommend doing an injector balance test. This will need to be done with a computer scanner with that capability. This will let you know which injector is failing.
FixItMan, Master Technician
Category: Car
Satisfied Customers: 17462
Experience: AA DEGREE AUTOMOTIVE/DIESEL TECH
FixItMan and 6 other Car Specialists are ready to help you
Customer: replied 5 years ago.
That was my thoughts too because I've tried everything else. The code confused me and that's probably the reason it hasn't showed back up. Thanks for your help!
No problem. The crank code can also be confusing and it can show up inder some very strange conditions. Please let me know what you find and if you need more help.