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02 Duramax sounds like an injector quit ??? How do I get a tech 2 ?

6.2 man

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I was driving my truck to work a few days ago .When I stopped at the stop sign I had a rough idle . Sounded like it was hitting on seven cylinders . There is no smoke . Parked the truck for a day and got a P 1093 c code . I cleared the code and took it out again . Truck seemed to run fine . Next day back to work ran fine . Got off the freeway and it idled bad again . Got to work and idled smooth again . Stopped before going home rough idle . Checked codes and the P 1093 was back . Stopped again before my house idled smooth . Parked truck rough idle again . Never seen any smoke .So what are the thoughts and would a tech 2 tell me where to start looking ? Where could I get a tech 2 scanner ? I am using a OTC genysis 3.0 .
 
This is one of the more common LB7 issues. There are a couple things which can cause this code to ring in:

1. Leaky fuel lines which allow air into the system
2. Failed fuel pressure regulator
3. Failed CP3 high pressure pump
4. High injector return rates

You can test the fuel lines by running a clean and clear tube as described in the post that Dean posted for you. Fuel pressure regulator you can check by inspecting the commanded vs actual fuel rail pressure and forcing the commanded value with a high quality scan tool like an EFIlive V2 or a Tech 2. CP3 pump can be checked by testing suction pressure and monitoring your fuel rail pressure at wide open throttle to ensure it doesn't drop off. Injector return rates are a bit of a hassle to check as you need to disassemble a good deal of the engine so you can connect return rail adapters and measure the volume of returned fuel over a given period of cranking time. Best just replace the injectors if you are going to go this deep into it.

Keep in mind that the high pressure pump and the injectors are quite expensive for these engines and also require a lot of labour to install. Sometimes it is cheaper, faster and easier to simply replace the entire engine with a good running used one vs repair what you've got.
 
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